Information storage/readout device for use in continuously manufacturing system for liquid-crystal display elements, and method and system for producing the same

ABSTRACT

An information storage/readout device for use in a system for continuously manufacturing liquid-crystal display elements comprises an information storage medium which stores therein slitting position information created based on the position of a defect detected by an inspection of a continuous polarizing composite film included in a continuous optical film laminate including a continuous polarizing composite film formed with an adhesive layer and a continuous carrier film releasably laminated on the adhesive layer, to indicate defective-polarizing-sheet slitting positions defining a defective or defect-containing polarizing sheet, and normal-polarizing-sheet slitting positions defining a normal or defect-free polarizing sheet, in the continuous inspected optical film laminate, and a roll of the continuous inspected optical film laminate which is provided with an identification indicia. In continuous manufacturing of liquid-crystal display elements, the present invention can dramatically enhance product accuracy and manufacturing speed and drastically improve product yield.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Divisional Application of U.S. patentapplication Ser. No. 12/903,977, filed Oct. 13, 2010, which claimspriority to Japanese patent application number 2009-236089, filed onOct. 13, 2009, which is incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to an information storage/readout devicefor use in a continuous manufacturing system for liquid-crystal displayelements, wherein the continuous manufacturing system is configured towork with a roll of a continuous optical film laminate which comprises acontinuous polarizing composite film including an adhesive layer andhaving a width conforming to a long or short side of a liquid-crystalpanel formed in a given size, and a continuous carrier film releasablylaminated on the adhesive layer, the system being operative to form aplurality of slits in the continuous optical film laminate fed out fromthe roll, along a direction perpendicular to a longitudinal directionthereof, to allow a plurality of polarizing sheets each having a givenlength corresponding to the long or short side of the liquid-crystalpanel to be sequentially cut from the continuous optical film laminateand laminated to respective ones of a plurality of liquid-crystal panelsso as to continuously manufacture liquid-crystal display elements. Morespecifically, the present invention relates to an informationstorage/readout device for use in the continuous manufacturing systemfor liquid-crystal display elements, wherein the informationstorage/readout device comprises an information storage medium whichstores therein slitting position information created based on theposition of a defect detected by an inspection of a continuouspolarizing composite film included in a continuous optical film laminateto indicate a defective-polarizing-sheet slitting position defining adefective or defect-containing polarizing sheet, and anormal-polarizing-sheet slitting position defining a normal ordefect-free polarizing sheet, and a roll of the continuous inspectedoptical film laminate which is provided with an identification means orindicia.

The present invention is further related to a method and system forproducing the information storage/readout device.

BACKGROUND ART

Taking a widescreen television having a diagonal screen size of 42inches as an example, a liquid-crystal panel W therefore comprises alayered liquid-crystal panel which includes a pair of rectangular-shapedglass substrates each having a size of about 540 to 560 mm inlength×about 950 to 970 mm in width×about 0.7 mm (700 μm) in thickness,and a liquid-crystal layer having a thickness of about 5 μm providedwith a transparent electrode, a color filter etc., and sandwichedbetween the glass substrates, as shown in FIG. 1. The thickness of theliquid-crystal panel W itself is about 1.4 mm (1400 μm). Theliquid-crystal display element is typically manufactured by laminating apolarizing composite film sheet 11″ including a polarizer and aprotective film to each of the front (viewing side) and back (backlightside) sides thereof. The polarizing composite film sheet 11″ is formed,for example, to have a dimension shown in FIG. 1 from a polarizingcomposite film 11 which is provided in the form of a flexible opticalfilm laminate 10 having a laminate structure.

For a liquid-crystal display element to function, the direction oforientation of liquid-crystal molecules and the direction ofpolarization of the polarizer are closely related each other. Inliquid-crystal display element technologies, LCDs (Liquid-crystalDisplay) using a TN (Twisted Nematic) type liquid-crystal have firstbeen put into practical use, and then LCDs using a VA (verticalAlignment) type liquid-crystal, an IPS (In-plane Switching) typeliquid-crystal etc., have been put into practical use. Although adetailed technical explanation is omitted, in an LCD using such TN-typeliquid-crystal panel, liquid-crystal molecules are provided between twoupper and lower orientation films having respective rubbing directionson the inner surfaces of glass substrates of the liquid-crystal panel.This means that the liquid-crystal molecules are twisted by 90 degreesalong the optical axis, so that when a voltage is applied, theliquid-crystal molecules are aligned in a direction perpendicular to theorientation of films. However, in the case where the LCD is designed toallow images as seen from right and left sides of a display screen asthose view directly in front of the display screen, the direction ofrubbing on the orientation film at the viewing-side must be 45 degrees(the rubbing direction of the other orientation film is 135 degrees). Itis therefore necessary that sheets of the polarizing composite films tobe laminated respectively on the front and back sides of theliquid-crystal panel must have polarizers respectively oriented indirections inclined by 45 degrees with respect to a lengthwise orwidthwise direction of the display screen so as to conform to therubbing directions.

Therefore, it is required that the optical film laminate is punched outor cut into a rectangular-shaped sheet having a long or short sidedetermined in accordance with the size of the TN liquid-crystal panel,in such a manner that the long or short side inclined by 45 degrees withrespect to the orientation direction of the polarizer. This procedure isdescribed in Japanese Laid-Open Patent Publication JP 2003-161935A(Patent Document 1) or Japanese Patent 3616866B (Patent Document 2), forexample. The sheet of such rectangular shape has a width or a short sidedimension which is smaller than the width of the optical film laminate.The rectangular-shaped sheets punched out or cut from the optical filmlaminate may be collectively referred as “individualized sheets.”

In producing a liquid-crystal display element using such individualizedsheets, each of the individualized sheets is punched out or cut inadvance together with a separator adhered to an adhesive layer. Theshaped individualized sheets are stored in a magazine in aliquid-crystal display element production system. The individualizedsheets stored in the magazine are taken out and conveyed one-by-one bymeans of a suction conveyance unit to the lamination position forlamination with respective ones of the liquid-crystal panels W. Beforebeing laminated to the liquid-crystal panel W, the separator releasablylaminated to a formed adhesive layer is peeled from respective ones ofthe individualized sheets, and each of the individualized sheets islaminated to the liquid-crystal panel W via as such exposed adhesivelayer. As the individualized sheets are flexible, they tend to be bowedor warped on their edges, and thus it is a serious technical impedimentin lamination with liquid-crystal panels. Thus, in producing aliquid-crystal display element using individualized sheets, it has beenrequired to adopt individualized sheets having four trimmed sides and acertain level of stiffness for less deflection or bend and which can beconveyed and laminated easily, to facilitate peeling respective ones ofseparators one-by-one and an accurate and swift positioning andlaminating respective ones of the individualized sheets withliquid-crystal panels. For this reason, the individualized sheets havebeen laminated with a protective film, for example, of 40 to 80 μm thicknot only to one surface but also to both surfaces of the polarizer tohave stiffness induced by the thickness. During the initial period inthe history of the manufacturing process of the liquid-crystal displayelements, the optical film sheet or a polarizing sheet comprised in suchoptical film sheet was generally known as “polarizing plate” which isstill used as a common name.

In the manufacturing process of TN-type liquid-crystal display elements,it is impossible to obtain finished liquid-crystal display elementssimply by sequentially laminating the sheets formed in the sequentialpunching or cutting process to respective ones of a plurality ofliquid-crystal panels in a subsequent process. This is because the sheetof the optical film laminate is cut from the web in such a manner thatthe sheet has a long or short side extending in a direction 45 degreeswith respect to the orientation direction of the polarizer which is thelongitudinal or stretching direction of the polarizer base film (i.e.,with respect to the feed direction of the optical film laminate prior tothe punching or cutting process), so that the sheet cannot be laminatedto respective ones of the liquid-crystal panels with the orientation asit has been cut from the web. Therefore, to laminate the sheets to theliquid-crystal panel, each of the sheets need to be punched-out at anangled direction of 45 degrees from the continuous web of the opticalfilm laminate having a width greater than a long side of theliquid-crystal panel with respect to the lengthwise direction of theoptical film laminate, using, for example, a die wider than a long sideof the liquid-crystal panel, and fed to the lamination station where thepolarizing sheets are laminated with the liquid-crystal panels, as seenin the Patent Document 1 or 2. Alternatively, the continuous opticalfilm laminate in use needs to be an elongated optical film laminatepreliminarily punched or cut from the continuous web of the optical filmlaminate having a substantially large width in a direction 45 degreesinclined with respect to the lengthwise direction, or an elongatedoptical film laminate formed with a plurality of formed sheets connectedinto a continuous film configuration. At any rate, the above methods donot provide any noticeable improvement over the method of usingindividualized sheets.

The Patent Document 3 is the Japanese Patent Publication No. 62-14810Bwhich discloses, prior to the VA-type liquid-crystal and the IPS-typeliquid-crystal being brought into practical use, an apparatus to producea liquid-crystal panel element. The apparatus is considered to be a typeof labeler unit which produces an LCD using the TN-type liquid-crystal.There is taught to provide an optical film laminate in the form of anelongated continuous optical film laminate having substantially largewidth and slit it in a direction 45 degrees oblique to the stretchingdirection of the polarizing composite film with a width corresponding tothe width of the liquid-crystal panel. Alternatively, a film-likeelongated optical film laminate sheet may be formed by longitudinallyconnecting a plurality of optical film laminate sheets. Therefore, themethod taught by the Patent Document 3 cannot be applied directly to amanufacturing process adapted to perform steps of continuously providinga plurality of polarizing composite film sheets from a continuousoptical film laminate and laminating the respective sheets to respectiveones of the liquid-crystal panels comprising VA-type or IPS-typeliquid-crystal.

Automation of manufacturing process for liquid-crystal display elementsusing individualized sheets is disclosed, for example, in the JapaneseLaid-Open Patent Publication JP 2002-23151A (Patent Document 4).Flexible individualized sheets tend to be bowed or warped due to curvesor distortion of their edges, and thus it is a serious technicalimpediment to accuracy and speed in registration and lamination withliquid-crystal panels. Thus, it will be understood that theindividualized sheet is required to have a certain level of thicknessand stiffness to facilitate registration and lamination withliquid-crystal panels typically in transportation under suction. Forexample, the disclosures in the Japanese Laid-Open Patent Publication JP2004-144913A (Patent Document 5), Japanese Laid-Open Patent PublicationJP 2005-298208A (Patent Document 6) or Japanese Laid-Open PatentPublication JP 2006-58411A (Patent Document 7) disclose measures foraddressing such technical problems.

In contrast to TN-type liquid-crystal panels, the VA-type and IPS-typeliquid-crystal panels are not designed to arrange liquid-crystalmolecules in twisted orientations. Thus, in the case of theliquid-crystal display element using these types of liquid-crystalpanels, there is no need to have the polarization axis of the polarizingsheet oriented at 45 degrees in view of viewing angle characteristicsinherent to the orientation of the liquid-crystal. Each of theseliquid-crystal display elements using these liquid-crystal panels isformed by applying polarizing sheets to the opposite sides of theliquid-crystal display panel oriented with their polarization axescrossed at 90 degrees crossing angle. In the case of the VA-type andIPS-type liquid-crystal panels, with respect to the technical view pointof symmetry of the viewing angle characteristics and visibility, maximumcontrast can be obtained along the direction of the polarizing axis ofthe polarizing sheet, so that it is preferable that the sheets havepolarizing axes oriented in parallel with the longitudinal or transversedirection of the liquid-crystal panel. Thus, it will be understood thatthese sheets to be applied to the liquid-crystal panel has a featurethat the continuous optical film laminate including a polarizingcomposite film which has been subjected to a longitudinal or transversestretching can be continuously fed out from a roll and cut alongtransverse lines with respect to the feed direction of the continuousoptical film laminate to sequentially produce rectangular polarizingsheets having the same width as the optical film laminate width.

Because of the improved viewing angle characteristics, forliquid-crystal used in a display element for widescreen televisions, theVA-type liquid-crystal or the IPS-type liquid-crystal are more widelyadopted than the TN type. In view of such trend in environments oftechnical developments, proposals to enhance the manufacturingefficiency using these types of liquid-crystal panels have been madesuch as the one described in Japanese Laid-Open Patent Publication JP2004-361741A (Patent Document 8). This patent discloses steps ofcontinuously feeding a continuous optical film laminate, cutting thecontinuous optical film laminate in conformity with the size of aliquid-crystal panel and sequentially laminating a plurality of opticalfilm sheets which have been produced by the cutting step to respectiveones of a plurality of the liquid-crystal panels.

However, the mainstream of manufacture of liquid-crystal displayelements is still based on the manufacturing technology utilizingindividualized sheets, due to the following technical problems. Inmanufacturing liquid-crystal display elements, a critical technicalchallenge is to detect any defect which may otherwise be retained in thedisplay elements to be formed, and to prevent any defective product frombeing produced. Most of the product defects primarily arise from defectsin the polarizing composite film contained in the continuous opticalfilm laminate. However, it is not practical to provide the continuousoptical film laminate after completely removing all defects contained inindividual films which are to be laminated together to form the opticalfilm laminate, because it is extremely difficult to produce adefect-free continuous optical film laminate under existingcircumstances. To maintain quality of display elements, it is notpermitted to use a polarizing composite film sheet having visible flawsor defects for a sheet for television display element even if such aflaw or defect is small. Given that the long side dimension of apolarizing sheet formed from the polarizing composite film is about 1 m,if a defective region cannot be preliminarily removed, 20 to 200defective liquid-crystal display elements out of 1,000 products will beproduced.

Proposals relating to preliminary inspection apparatus for a polarizingcomposite film have previously been made, as disclosed, for example, inJapanese Patent No. 3974400B (Patent Document 9), Japanese Laid-OpenPatent Publications JP 2005-62165A (Patent Document 10) and JP2007-64989A (Patent Document 11) for improving the production efficiencyof manufacturing the individualized sheets. These proposals havedisclosed technical means essential to improving yield in themanufacture of such individualized sheets.

Further, Japanese Laid-Open Patent Publications JP 2007-140046A (PatentDocument 12) discloses a method comprising the steps of exposing apolarizing composite film having an adhesive layer by peeling a carrierfilm included in the continuous optical film laminate continuously fedout from a roll of continuous optical film laminate, detecting a defector defects present in the polarizing composite film, punching onlynormal regions of the polarizing composite film in rectangular shape,appropriately avoiding defective regions, and conveying the punchednormal polarizing sheets to the lamination position for lamination withthe liquid-crystal panels by other conveying medium. It should howeverbe noted that this process is not the one which makes it possible tofeed the normal optical film sheets formed from a continuous opticalfilm laminate to the lamination position for lamination with theliquid-crystal panel by means of the carrier film. This technique is amethod for once laminating the cut individualized sheets to otherconveying medium before conveying to the lamination position with theliquid-crystal panels, so this technique is not beyond theindividualized sheet manufacturing system of liquid-crystal displayelement.

Japanese Laid-Open Patent Publications JP 2009-061498A (Patent Document13) discloses a method for laminating the sheets of the optical filmlaminate with the liquid-crystal panels and an apparatus therefore. Thisinvention contains an innovative proposal allowing for shifting from aliquid-crystal display element manufacturing system designed to carry aplurality of preliminary formed individualized sheets in themanufacturing process of the liquid-crystal display element, andlaminate the individualized sheets one by one to respective ones of aplurality of liquid-crystal panels, to a continuous manufacturing systemfor liquid-crystal display element designed to continuously form aplurality of optical film sheets and directly laminate the formed sheetsto respective ones of a plurality of liquid-crystal panels.

However, the method and system disclosed cause not only substantialcomplexity in the entire system for laminating but also an increase inthe number of steps and difficulty in control for each step, and thuscauses reduction in the manufacturing speed.

The present invention has been made in view of the aforementionedproblems in the prior proposals and through intensive researches andconsiderations for enabling a continuous manufacturing of liquid-crystaldisplay elements, provides a method and system for significantlyenhancing product accuracy and manufacturing speed, and drasticallyimproving manufacturing yield, in the manufacture of liquid-crystaldisplay elements.

The prior art documents referred to in the above descriptions are listedbelow.

Patent Document 1: Japanese Laid-Open Patent Publication JP 2003-161935A

Patent Document 2: Japanese Patent No. 3616866B

Patent Document 3: Japanese Patent Publication 62-14810B

Patent Document 4: Japanese Laid-Open Patent Publication JP 2002-23151A

Patent Document 5: Japanese Laid-Open Patent Publication JP 2004-144913A

Patent Document 6: Japanese Laid-Open Patent Publication JP 2005-298208A

Patent Document 7: Japanese Laid-Open Patent Publication JP 2006-58411A

Patent Document 8: Japanese Laid-Open Patent Publication JP 2004-361741A

Patent Document 9: Japanese Patent No. 3974400B

Patent Document 10: Japanese Laid-Open Patent Publication JP 2005-62165A

Patent Document 11: Japanese Laid-Open Patent Publication JP 2007-64989A

Patent Document 12: Japanese Laid-Open Patent Publication JP2007-140046A

Patent Document 13: Japanese Laid-Open Patent Publication JP2009-061498A

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

The VA-type and IPS-type liquid-crystal panels are advantageous overTN-type liquid-crystal panels from the viewpoint of manufacture in thatthere is no restriction in the VA and IPS-types that two polarizingsheets are required to be laminated to respective ones of front and rearsurfaces of the liquid-crystal panel in 45 degrees oblique with respectto the polarization axis of the polarizing sheet on the respective sidesof the liquid-crystal display element, as experienced in the manufactureof TN-type liquid-crystal panels, due to the viewing anglecharacteristics inherent to the orientation of the liquid-crystal.Therefore, it is possible to carry out a process for continuouslymanufacturing liquid-crystal display elements using the VA-type andIPS-type liquid-crystal panels, while feeding a continuous optical filmlaminate, by continuously laminating the polarizing composite filmsheets prepared by cutting the optical film laminate in the transversedirection with respect to the feed direction of the optical filmlaminate with the respective ones of a plurality of the liquid-crystalpanels. In addition, during the feed of the optical film laminate, ifnormal polarizing sheets having no defect and defective ordefect-containing polarizing sheets having defects detected through thepreliminary inspection of a continuous polarizing composite film arebeing cut out, and if only the normal polarizing sheets are laminated torespective ones of a plurality of liquid-crystal panels to makeliquid-crystal display elements, without interrupting the feed of theoptical film laminate, it becomes possible to obtain enhanced productaccuracy and manufacturing speed as well as significantly improvedproduction yield in the manufacture of liquid-crystal display elements.

It is an object of the present invention to provide means for subjectingto a preliminary inspection, a continuous optical film laminatecomprising a continuous polarizing composite film with an adhesivelayer, and a continuous carrier film releasably laminated on theadhesive layer, to inspect the continuous polarizing sheet (thecontinuous optical film laminate subjected to the preliminary inspectionwill hereinafter be referred to as “continuous inspected optical filmlaminate), in such a manner as to allow a defective polarizing sheetcontaining a defect detected by the preliminary inspection, and adefect-free, normal polarizing sheet, to be continuously cut from thecontinuous inspected optical film laminate being fed toward a laminationstation, and preventing the defective polarizing sheet from beinglaminated to a liquid-crystal panel, whereby means for continuouslylaminating only a plurality of the normal polarizing sheets torespective ones of a plurality of the liquid-crystal panels withoutinterrupting the feeding of the continuous inspected optical filmlaminate is achieved to dramatically enhance product accuracy andmanufacturing speed and drastically improve product yield, in acontinuous manufacturing process for liquid-crystal display elements.

Means for Solving the Problem

The above object can be achieved by providing an information storagemedium which stores therein slitting position information created basedon a position of a defect detected by preliminarily inspecting acontinuous polarizing composite film included in a continuous opticalfilm laminate to indicate defective-polarizing-sheet slitting positionsdefining a defective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in a continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification means or indicia, in such amanner as to allow a plurality of the normal polarizing sheets to be cutfrom the continuous inspected optical film laminate being fed out fromthe roll, based on the slitting position information read out from theinformation storage medium in accordance with reading of theidentification means or indicia from the continuous inspected opticalfilm laminate, and laminated to respective ones of a plurality ofliquid-crystal panels.

In one aspect of the present invention, there is provided an informationstorage/readout device for use in a continuous manufacturing system forliquid-crystal display elements, wherein the continuous manufacturingsystem is provided with a roll of a continuous optical film laminatewhich comprises a continuous polarizing composite film including anadhesive layer and having a width conforming to a long or short side ofa liquid-crystal panel formed in a given size, and a continuous carrierfilm releasably laminated on the adhesive layer, and designed to form aplurality of slits in the continuous optical film laminate fed out fromthe roll, along a direction perpendicular to a longitudinal directionthereof, to allow a plurality of polarizing sheets each having a givenlength corresponding to the long or short side of the liquid-crystalpanel to be sequentially cut from the continuous optical film laminateand laminated to respective ones of a plurality of the liquid-crystalpanels so as to continuously manufacture liquid-crystal displayelements. The information storage/readout device comprises aninformation storage medium which stores therein slitting positioninformation created based on a position of a defect detected by aninspection of a continuous polarizing composite film included in acontinuous optical film laminate to indicate defective-polarizing-sheetslitting positions defining a defective or defect-containing polarizingsheet, and normal-polarizing-sheet slitting positions defining a normalor defect-free polarizing sheet, in the continuous inspected opticalfilm laminate, and a roll of the continuous inspected optical filmlaminate which is provided with an identification means or indicia,wherein the continuous manufacturing system is operable, based on theslitting position information read out from the information storagemedium in accordance with reading of the identification means or indiciafrom the continuous inspected optical film laminate, and distancemeasurement data obtained from a feed distance of the continuousinspected optical film laminate from the roll, to form a plurality ofslits in the continuous inspected optical film laminate from a surfaceopposite to the continuous carrier film to a depth reaching a surface ofthe continuous carrier film adjacent to the adhesive layer, to allow aplurality of the normal polarizing sheets each having a lengthcorresponding to the long or short side of the liquid-crystal panel tobe cut from the continuous inspected optical film laminate, andlaminated to respective ones of a plurality of the liquid-crystalpanels.

In one embodiment of the present invention, the continuous inspectedoptical film laminate further comprises a continuous surface protectionfilm releasably laminated on the continuous polarizing composite film ata surface opposite to the adhesive layer.

According to another aspect of the present invention, there is provideda method for producing an information to be stored in a storage/readoutdevice for use in a continuous manufacturing system for liquid-crystaldisplay elements, wherein the continuous manufacturing system isprovided with a roll of a continuous optical film laminate whichcomprises a continuous polarizing composite film including an adhesivelayer and having a width conforming to a long or short side of aliquid-crystal panel formed in a given size, and a continuous carrierfilm releasably laminated on the adhesive layer, and designed to form aplurality of slits in the continuous optical film laminate fed out fromthe roll, along a direction perpendicular to a longitudinal directionthereof, to allow a plurality of polarizing sheets each having a givenlength corresponding to the long or short side of the liquid-crystalpanel to be sequentially cut from the continuous optical film laminateand laminated to respective ones of a plurality of the liquid-crystalpanels so as to continuously manufacture liquid-crystal displayelements, and the information storage/readout device comprises aninformation storage medium which stores therein slitting positioninformation created based on a position of a defect detected by aninspection of a continuous polarizing composite film included in acontinuous optical film laminate to indicate adefective-polarizing-sheet slitting position defining a defective ordefect-containing polarizing sheet, and a normal-polarizing-sheetslitting position defining a normal or defect-free polarizing sheet, inthe continuous inspected optical film laminate; and a roll of thecontinuous inspected optical film laminate which is provided with anidentification means or indicia. The method comprises the steps oflaminating a continuous protective film on at least one of oppositesurfaces of a continuous polarizer to form a continuous polarizingcomposite film on which the adhesive layer is not yet formed, inspectingthe continuous polarizing composite film on which the adhesive layer isnot yet formed to detect any defect contained in the continuouspolarizing composite film on which the adhesive layer is not yet formed,creating, based on the position of the defect in the continuouspolarizing composite film on which the adhesive layer is not yet formed,the slitting position information indicative of the normal polarizingsheet-slitting positions and the defective polarizing sheet-slittingpositions defining respectively the normal polarizing sheet and thedefective polarizing sheet in a direction perpendicular to thelongitudinal direction of the continuous polarizing composite film,releasably laminating a continuous carrier film to the continuousinspected polarizing composite film through an adhesive layer to formthe continuous inspected optical film laminate, storing the slittingposition information in a storage medium, in a manner usable by thecontinuous manufacturing system to, during feeding of the continuousinspected optical film laminate, form a plurality of slits in thecontinuous inspected optical film laminate along a directionperpendicular to the longitudinal direction from a surface opposite tothe continuous carrier film to a depth reaching a surface of thecontinuous carrier film adjacent to the adhesive layer so as to make itpossible to cut the normal polarizing sheet and the defective polarizingcomposite film from the continuous inspected optical film laminateindividually, creating the identification means or indicia inassociation with the slitting position information and providing theidentification means or indicia on the continuous inspected optical filmlaminate, and winding the continuous inspected optical film laminateprovided with the identification means or indicia, into a roll toprovide the roll of the continuous optical film laminate

In one embodiment of the present invention, the step of forming thecontinuous inspected optical film laminate includes a sub-step ofreleasably laminating a continuous surface protection film on thecontinuous inspected polarizing composite film at a surface opposite tothe adhesive layer.

In another embodiment of the present invention, the step of detecting adefect contained in the continuous polarizing composite film includesone or a combination of sub-steps of primarily inspecting a surface ofthe continuous polarizing composite film on which the adhesive layer isnot yet formed by means of reflected light, transmitting lightirradiated from a light source through the continuous polarizingcomposite film on which the adhesive layer is not yet formed to detectany defect existing in the continuous polarizing composite film on whichthe adhesive layer is not yet formed as a shade, and arranging thecontinuous polarizing composite film and a polarization filter to haveabsorption axes thereof to be set in a cross-Nicol arrangement,projecting light from a light source thereto, and observing lighttransmitted therethrough to detect any defect in the continuouspolarizing composite film as a bright spot.

According to still further aspect of the present invention, there isprovided a method for producing an information storage/readout devicefor use in a continuous manufacturing system for liquid-crystal displayelements, wherein the continuous manufacturing system is configured towork with a roll of a continuous optical film laminate which comprises acontinuous polarizing composite film formed with an adhesive layer andhaving a width conforming to a long or short side of a liquid-crystalpanel formed in a given size, and a continuous carrier film releasablylaminated on the adhesive layer, and operate to form a plurality ofslits in the continuous optical film laminate fed out from the roll,along a direction perpendicular to a longitudinal direction thereof, toallow a plurality of polarizing sheets each having a given lengthcorresponding to the long or short side of the liquid-crystal panel tobe sequentially cut from the continuous optical film laminate andlaminated to respective ones of a plurality of liquid-crystal panels soas to continuously manufacture liquid-crystal display elements, andwherein the information storage/readout device comprises an informationstorage medium which stores therein slitting position informationcreated based on the position of a defect detected by an inspection of acontinuous polarizing composite film included in a continuous opticalfilm laminate to indicate defective-polarizing-sheet slitting positionsdefining a defective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in the continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification means or indicia. The methodcomprises the steps of preparing a roll of a continuous provisionaloptical film laminate which comprises a continuous polarizing compositefilm formed with an adhesive layer, and a continuous provisional carrierfilm releasably laminated on the adhesive layer, peeling the continuousprovisional carrier film while feeding the continuous provisionaloptical film laminate out from the roll, to expose the continuouspolarizing composite film including adhesive layer, inspecting a surfaceand inside of the continuous polarizing composite film including exposedadhesive layer to detect any defect contained in the continuouspolarizing composite film including adhesive layer, creating based onthe position of the defect in the continuous polarizing composite filmincluding adhesive layer, the slitting position information indicativeof the normal polarizing sheet-slitting positions and the defectivepolarizing sheet-slitting positions defining respectively the normalpolarizing sheet and the defective polarizing sheet in a directionperpendicular to a longitudinal direction of the continuous polarizingcomposite film including adhesive layer, releasably laminating acontinuous carrier film on the exposed adhesive layer of the continuousinspected polarizing composite film to form the continuous inspectedoptical film laminate, storing the slitting position information in theinformation storage medium, in a manner usable by the continuousmanufacturing system to, during feeding of the continuous inspectedoptical film laminate, form a plurality of slits in the continuousinspected optical film laminate along a direction perpendicular to thelongitudinal direction from a surface opposite to the continuous carrierfilm to a depth reaching a surface of the continuous carrier filmadjacent to the adhesive layer so as to make it possible to cut thenormal polarizing sheet and the defective polarizing composite film fromthe continuous inspected optical film laminate individually, creatingthe identification means or indicia in association with the slittingposition information and providing the identification means or indiciaon the continuous inspected optical film laminate, and winding thecontinuous inspected optical film laminate provided with theidentification means or indicia, into a roll to provide the roll of thecontinuous optical film laminate.

In one embodiment of the present invention, the continuous provisionalcarrier film has a transferable adhesive layer formed by subjecting onesurface of the continuous provisional carrier film to a releasingtreatment, applying a solvent containing an adhesive to the treatedsurface, and drying the solvent.

In another embodiment of the present invention, the surface of thecontinuous carrier film laminated on the exposed adhesive layer of thecontinuous inspected polarizing composite film is preliminarilysubjected to a releasing treatment.

In yet another embodiment of the present invention, the step of formingthe continuous inspected optical film laminate includes a sub-step ofreleasably laminating a continuous surface protection film on thecontinuous inspected polarizing composite film at a surface opposite tothe adhesive layer.

In accordance with still another embodiment of the present invention,the step of detecting a defect contained in the continuous polarizingcomposite film includes one or a combination of sub-steps of primarilyinspecting a surface of the continuous polarizing composite filmincluding adhesive layer by means of reflected light, a sub-step oftransmitting light irradiated from a light source through the continuouspolarizing composite film with an adhesive layer provided thereon todetect a defect contained in the continuous polarizing composite film asa shade, and arranging the continuous polarizing composite film and apolarization filter to have absorption axes thereof to be set in across-Nicol arrangement, projecting light from a light source thereto,and observing light transmitted therethrough to detect any defectcontained in the continuous polarizing composite film as a bright spot.

According to still further aspect of the present invention, there isprovided a system for producing an information storage/readout devicefor use in a continuous manufacturing system for liquid-crystal displayelements, wherein the continuous manufacturing system is configured towork with a roll of a continuous optical film laminate which comprises acontinuous polarizing composite film having an adhesive layer providedon one surface thereof and having a width conforming to a long or shortside of a liquid-crystal panel formed in a given size, and a continuouscarrier film releasably laminated on the adhesive layer, and operates toform a plurality of slits in the continuous optical film laminate fedout from the roll, along a direction perpendicular to a longitudinaldirection thereof, to make it possible to sequentially cut a pluralityof polarizing sheets each having a given length corresponding to thelong or short side of the liquid-crystal panel from the continuousoptical film laminate and to laminate to respective ones of a pluralityof the liquid-crystal panels so as to continuously manufactureliquid-crystal display elements, and wherein the informationstorage/readout device comprises an information storage medium whichstores therein slitting position information created based on theposition of a defect detected by an inspection of a continuouspolarizing composite film included in a continuous optical film laminateto indicate defective-polarizing-sheet slitting positions defining adefective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in the continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification means or indicia. The systemcomprises a polarizing composite film-forming unit adapted to laminate acontinuous protective film on at least one of opposite surfaces of acontinuous polarizer to form an continuous polarizing composite film onwhich the adhesive layer is not yet formed, an inspection unit adaptedto inspect the continuous polarizing composite film on which theadhesive layer is not yet formed to detect any defect contained in thecontinuous polarizing composite film on which the adhesive layer is notyet formed, slitting position information-creating means adapted to,based on the position of the defect in the continuous polarizingcomposite film on which the adhesive layer is not yet formed, create theslitting position information indicative of the normal polarizingsheet-slitting positions and the defective polarizing sheet-slittingpositions defining respective ones of the normal polarizing sheet andthe defective polarizing sheet in a direction perpendicular to alongitudinal direction of the continuous polarizing composite film onwhich the adhesive layer is not yet formed, a continuous inspectedoptical film laminate forming unit adapted to releasably laminate acontinuous carrier film to the continuous inspected polarizing compositefilm through an adhesive layer to form the continuous inspected opticalfilm laminate, an information storage medium forming unit adapted tostore the slitting position information in the information storagemedium, in a manner usable by the continuous manufacturing system to,during feeding of the continuous inspected optical film laminate, form aplurality of slits in the continuous inspected optical film laminatealong a direction perpendicular to the longitudinal direction from asurface opposite to the continuous carrier film to a depth reaching asurface of the continuous carrier film adjacent to the adhesive layer soas to make it possible to cut the normal polarizing sheet and thedefective polarizing sheet from the continuous inspected optical filmlaminate individually, an identification providing unit adapted tocreate the identification means or indicia in association with theslitting position information and provide the identification means orindicia on the continuous inspected optical film laminate, a taking upunit adapted to wind the continuous inspected optical film laminatehaving the identification means or indicia, into a roll to form the rollof the continuous optical film laminate; and a control unit adaptedcontrol respective operations of at least the polarizing composite filmforming unit, the inspection unit, the slitting position informationcreating means, the continuous inspected optical film laminate formingunit, the information storage medium forming unit, the identificationproviding unit and the taking up unit, in an inter-related manner

In one embodiment of the present invention, the continuous inspectedoptical film laminate forming unit includes a surface protection filmfeed device adapted to releasably laminate a continuous surfaceprotection film on the continuous inspected polarizing composite film ata surface opposite to the adhesive layer.

In another embodiment of the present invention, the inspection unitincludes one or a combination of a first inspection device adapted toprimarily inspect a surface of the continuous polarizing composite filmon which the adhesive layer is not yet formed by means of reflectedlight, a second inspection device adapted to transmit light irradiatedfrom a light source through the continuous polarizing composite film onwhich the adhesive layer is not yet formed to detect a defect containedin the continuous polarizing composite film as a shade, and a thirdinspection device adapted to arrange the continuous polarizing compositefilm on which the adhesive layer is not yet formed and a polarizationfilter to have absorption axes thereof to be set in a cross-Nicolarrangement, emitting light from a light source thereto, and observinglight transmitted therethrough to detect a defect contained in thecontinuous polarizing composite film as a bright spot.

According to still further aspect of the present invention, there isprovided a system for producing an information storage/readout devicefor use in a continuous manufacturing system for liquid-crystal displayelements, wherein the continuous manufacturing system is configured towork with a roll of a continuous optical film laminate which comprises acontinuous polarizing composite film having an adhesive layer providedon one surface thereof and having a width conforming to a long or shortside of a liquid-crystal panel formed in a given size, and a continuouscarrier film releasably laminated on the adhesive layer, and operate toform a plurality of slits in the continuous optical film laminate fedout from the roll, along a direction perpendicular to a longitudinaldirection thereof, to make it possible to be sequentially cut aplurality of polarizing sheets each having a given length correspondingto the long or short side of the liquid-crystal panel from thecontinuous optical film laminate and laminate to respective ones of aplurality of the liquid-crystal panels so as to continuously manufactureliquid-crystal display elements, and wherein the informationstorage/readout device comprises an information storage medium whichstores therein slitting position information created based on theposition of a defect detected by an inspection of a continuouspolarizing composite film included in a continuous optical film laminateto indicate defective-polarizing-sheet slitting positions defining adefective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in the continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification means or indicia. The systemcomprises a provisional optical film laminate feed unit provided with aroll of a continuous provisional optical film laminate which comprises acontinuous polarizing composite film having an adhesive layer providedon one surface thereof, and a continuous provisional carrier filmreleasably laminated on the adhesive layer, and adapted to feed thecontinuous provisional optical film laminate out from the roll, aprovisional carrier film peeling unit adapted to peel the continuousprovisional carrier film from the continuous provisional optical filmlaminate being fed out from the roll, to have the adhesive layer on thecontinuous polarizing composite film exposed, an inspection unit adaptedto inspect a surface and inside of the continuous polarizing compositefilm having the exposed adhesive layer to detect a defect contained inthe continuous polarizing composite film including adhesive layer,slitting position information creating means adapted to, based on theposition of the defect in the continuous polarizing composite filmincluding adhesive layer, create the slitting position informationindicative of the normal polarizing sheet-slitting positions and thedefective polarizing sheet-slitting positions defining respective onesof the normal polarizing sheet and the defective polarizing sheet in adirection perpendicular to a longitudinal direction of the continuouspolarizing composite film including the adhesive layer, a continuousinspected optical film laminate forming unit adapted to releasablylaminate a continuous carrier film on the exposed adhesive layer of thecontinuous polarizing composite film to form the continuous inspectedoptical film laminate, an information storage medium forming unitadapted to store the slitting position information in the informationstorage medium, in a manner usable by the continuous manufacturingsystem to, during feeding of the continuous inspected optical filmlaminate, form a plurality of slits in the continuous inspected opticalfilm laminate along a direction perpendicular to the longitudinaldirection from a surface opposite to the continuous carrier film to adepth reaching a surface of the continuous carrier film adjacent to theadhesive layer so as to make it possible to cut the normal polarizingsheet and the defective polarizing sheet from the continuous inspectedoptical film laminate individually, an identification providing unitadapted to create the identification means or indicia in associationwith the slitting position information and provide the identificationmeans or indicia on the continuous inspected optical film laminate, ataking up unit adapted to wind the continuous inspected optical filmlaminate provided with the identification means or indicia, into a rollto provide the roll of the continuous optical film laminate, and acontrol unit adapted control respective operations of at least theprovisional optical film laminate feed unit, the provisional carrierfilm peeling unit, the inspection apparatus, the slitting positioninformation creating means, the continuous inspected optical filmlaminate forming unit, the information storage medium forming unit, theidentification providing unit and the taking up unit, in aninter-related manner.

In one embodiment of the present invention, the continuous provisionalcarrier film has a transferable adhesive layer formed by subjecting onesurface of the provisional carrier film to a releasing treatment,applying a solvent containing an adhesive to the treated surface, anddrying the solvent.

In another embodiment of the present invention, the continuous carrierfilm is subjected to a releasing treatment at a surface laminated on theexposed adhesive layer of the continuous inspected polarizing compositefilm

In yet another embodiment of the present invention, the continuousinspected optical film laminate-forming unit includes a surfaceprotection film feed device adapted to releasably laminate a continuoussurface protection film on a surface of the continuous inspectedpolarizing composite film on an opposite side of the adhesive layer.

In still another embodiment of the present invention, the inspectionunit includes one or any combination of a first inspection deviceadapted to primarily inspect a surface of the continuous polarizingcomposite film having an adhesive layer provided on one surface thereofby means of reflected light, a second inspection device adapted totransmit light irradiated from a light source through the continuouspolarizing composite film having such adhesive layer to detect a defectcontained in the continuous polarizing composite film as a shade, and athird inspection device adapted to arrange the continuous polarizingcomposite film having such adhesive layer and a polarization filter tohave absorption axes thereof to be set in a cross-Nicol arrangement,emitting light from a light source thereto, and observing lighttransmitted therethrough to detect any defect contained in thecontinuous polarizing composite film as a bright spot.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 illustrates a typical example of a liquid-crystal display elementfor a widescreen television having a diagonal screen size of 42 inches.

FIG. 2 is a schematic diagram showing a structure of a continuousoptical film laminate for use in manufacturing of liquid-crystal displayelements, in the present invention.

FIG. 3 is a schematic diagram showing a defect-free, normal region(corresponding to a normal-polarizing-sheet slitting position defining anormal polarizing sheet) and a defective region (corresponding to adefective-polarizing-sheet slitting position defining a defectivepolarizing sheet) containing a defect contained in a continuouspolarizing composite film included in a continuous inspected opticalfilm laminate for use in manufacturing of liquid-crystal displayelements in the present invention.

FIG. 4 is a conceptual diagram showing a continuous manufacturing systemfor liquid-crystal display element 1, in one embodiment of the presentinvention, wherein the system 1 comprises an optical film laminate feedunit 100 for feeding a continuous inspected optical film laminate from aroll R thereof provided therein, and a liquid-crystal panel conveyanceunit 300 for conveying a liquid-crystal panel to be laminated with anormal polarizing sheet cut from the continuous inspected optical filmlaminate by forming slits in the continuous inspected optical filmlaminate based on slitting position information read out from aninformation storage medium.

FIG. 5 is a flowchart showing a manufacturing process or process stepsin the continuous manufacturing system illustrated in FIG. 4.

FIG. 6 is a schematic diagram showing a method and system for producinga roll R of a continuous inspected optical film laminate provided withan identification means or indicia associated with the slitting positioninformation stored in the information storage medium, according to oneembodiment of the present invention.

FIG. 7 is a flowchart showing a production process in the method andsystem for producing the roll R, illustrated in FIG. 6.

FIG. 8 is a schematic diagram showing a method and system for producinga roll R of a continuous inspected optical film laminate provided withan identification means or indicia associated with the slitting positioninformation stored in the information storage medium, using a roll R′ ofa continuous provisional optical film laminate, according to anotherembodiment of the present invention.

FIG. 9 is a flowchart showing a production process in the method andsystem for producing the roll R, illustrated in FIG. 8.

FIG. 10 is a schematic diagram showing a relationship between theidentification means or indicia read from the continuous inspectedoptical film laminate, and the slitting position information read outfrom the information storage medium in accordance with reading of theidentification means or indicia, in the system 1 illustrated in FIG. 4,using an information storage/readout device according to one embodimentof the present invention, which comprises the information storage mediumstoring therein the slitting position information created for thecontinuous inspected optical film laminate by the production system forthe Roll R, illustrated in FIG. 6 or 8, and the roll of the continuousinspected optical film laminate provided with the identification meansor indicia associated with the slitting position information.

FIG. 11 is a schematic diagram showing a defective polarizing sheetremoval unit of the system 1, wherein the defective polarizing sheetremoval unit comprises (1) a dummy film drive mechanism disposed in afeed passage for an optical film laminate or (2) a dummy film drivemechanism adapted to be moved in and away from a gap between a pair oflamination rollers movable closer to and away from each other.

FIG. 12 is a schematic diagram showing an operation of a slittingposition check-up unit of the system 1, wherein the slitting positioncheck-up unit is adapted to check a position of a slit formed in thecontinuous inspected optical film laminate being fed, based on distancemeasurement data obtained from a feed distance of the continuousinspected optical film laminate, and the slitting position informationread out in accordance with reading of the identification mean orindicia provided on the continuous inspected optical film laminate.

FIG. 13 is a schematic diagram showing an operation of conveying aliquid-crystal panel in a posture controlled by a pre-alignment unit, afinal-alignment unit, a final conveyance unit and a panel-edge detectionunit in the liquid-crystal panel conveyance unit, before laminating tothe liquid-crystal panel a normal polarizing sheet cut into a givenlength corresponding to that of the liquid-crystal panel, in the system1.

FIG. 14 is a schematic diagram showing a lamination unit which comprisesa edge detection unit for detecting a leading edge of a normalpolarizing sheet cut from the continuous inspected optical film laminateillustrated in FIG. 13 into a given length corresponding to that of aliquid-crystal panel, and straight ahead posture detection unit fordetecting an alignment between a straight ahead posture of the normalpolarizing sheet and a feed direction.

FIG. 15 is a table showing a type, contents, etc., of identificationmeans or indicia to be provided on the continuous inspected optical filmlaminate.

FIG. 16 is a schematic diagram showing a process of creating theslitting position information for the continuous inspected optical filmlaminate, by calculating a defective polarizing sheet slitting positiondefining a defective or defect-containing polarizing sheet and a normalpolarizing sheet slitting position defining a normal or defect-freepolarizing sheet, based on a position of a defect in the continuousinspected optical film laminate, in a method for producing theinformation storage/readout device, according to one embodiment of thepresent invention.

FIG. 17 is a flowchart showing a process of calculating a defectivepolarizing sheet slitting position defining a defective ordefect-containing polarizing sheet and a normal polarizing sheetslitting position defining a normal or defect-free polarizing sheet,based on a position of a defect in the continuous inspected optical filmlaminate.

FIG. 18 is a flowchart showing another process of calculating adefective polarizing sheet slitting position defining a defective ordefect-containing polarizing sheet and a normal polarizing sheetslitting position defining a normal or defect-free polarizing sheet,based on a position of a defect in the continuous inspected optical filmlaminate.

FIG. 19 is a flowchart showing yet another process of calculating adefective polarizing sheet slitting position defining a defective ordefect-containing polarizing sheet and a normal polarizing sheetslitting position defining a normal or defect-free polarizing sheet,based on a position of a defect in the continuous inspected optical filmlaminate.

FIG. 20 illustrates one example of the slitting position information,corresponding to a technique of storing defective polarizing sheetidentification information Xγ in FIG. 17.

FIG. 21 illustrated one example of the slitting position information,corresponding to a technique of setting a distance to a next slittingposition to ((x′+x₀), wherein (x′>x₀, in FIG. 18.

FIG. 22 illustrates one example of the slitting position information,corresponding to a technique of setting a distance to a next slittingposition to [(x′+x₀)/m], wherein m=±2 or more, in FIG. 19.

FIG. 23 is a table showing a defect inspection device, a type of defectand a defect detection method.

DESCRIPTION OF EMBODIMENTS

In the context of the description, a continuous film comprising acontinuous polarizer laminated with a continuous protective film on oneor each surface and formed with an adhesive layer on the surface to belaminated with a liquid-crystal panel is referred as “a continuouspolarizing composite film,” and a sheet having a rectangular shape andformed from the continuous polarizing composite film is referred as “apolarizing composite film sheet” or simply “a sheet,” rather than thecommonly called name “polarizing plate.” In addition, when a sheet isformed from a continuous polarizing composite film having a continuoussurface-protection film and a continuous carrier film attached thereto,and when this sheet has to be distinguished from “a polarizing compositefilm sheet”, it is referred as “an optical film laminate sheet”, and asheet formed from the continuous surface-protection film or thecontinuous carrier film included in the continuous polarizing compositefilm is respectively referred as “a surface-protection film sheet” or “acarrier film sheet” respectively.

The present invention will now be described with reference to specificembodiments illustrated in the accompanying drawings.

1. Configuration of a System for Continuous Manufacturing Liquid-CrystalDisplay Elements

FIG. 4 is a schematic diagram showing a system for continuousmanufacturing liquid-crystal display element. The system 1 is providedwith a roll R of a continuous inspected optical film laminate whichcomprises a continuous polarizing composite film having an adhesivelayer provided on one surface thereof and having a width conforming to along or short side of a liquid-crystal panel, and a continuous carrierfilm releasably laminated on the adhesive layer, wherein the continuousinspected optical film laminate is provided with an identification meansor indicia 20 associated with slitting position information 80 which iscreated based on the position of a defect detected by an inspection of acontinuous polarizing composite film before the adhesive layer isapplied thereto or a continuous polarizing composite film having anadhesive layer provided on one surface thereof, and pre-stored in aninformation storage medium 800. The system 1 comprises an optical filmlaminate feed unit 100 for continuously feeding the continuous inspectedoptical film laminate from the roll R. The information storage medium800 stores therein the slitting position information 80 which is createdduring a process of producing the continuous inspected optical filmlaminate provided with the identification means or indicia 20, based ona position of a defect detected by an inspection of a continuouspolarizing composite film without the adhesive layer or a continuouspolarizing composite film formed with the adhesive layer to indicatedefective-polarizing-sheet slitting positions defining a defective ordefect-containing polarizing sheet, and normal-polarizing-sheet slittingpositions defining a normal or defect-free polarizing sheet, in thecontinuous inspected optical film laminate, as will be described later.The information storage medium 800 may be comprised of a flexible disk,a CD, a DVD, a flash memory or a hard disk. The slitting positioninformation 80 created based on the position of a defect detected by aninspection of a continuous polarizing composite film may be transferredto a storage device 420 of the system 1 directly via the Internet or adedicated line, without involving the information storage medium 800,just after the slitting position information 80 is created in aproduction system for the roll R which will be described later. In thiscase, the storage device 420 functions as “information storage medium”set forth in the appended claims. The system 1 further comprises aliquid-crystal panel conveyance unit 300 for sequentially conveying aplurality of liquid-crystal panels to be laminated with respective onesof a plurality of a normal polarizing sheets cut from the continuousinspected optical film laminate into a given length corresponding to along or short side of the liquid-crystal panel by forming a plurality ofslits in the continuous inspected optical film laminate based on theslitting position information 80 read out from the information storagemedium 800 or the storage device 420. The system 1 further comprises acontrol unit 400 for generally controlling operations of the opticalfilm laminate feed unit 100 and the liquid-crystal panel conveyance unit300.

The optical film laminate feed unit 100 has a slitting station A forcutting a plurality of polarizing sheets 11″ from the continuousinspected optical film laminate, a removal station C for removing one ormore of the defective polarizing sheets 11″, and a lamination station Bfor laminating normal ones of the cut polarizing sheets 11″ torespective ones of a plurality of liquid-crystal panels. The opticalfilm laminate feed unit 100 may have the removal station C and thelamination station B in an overlapped arrangement, as will be describedlater. The liquid-crystal panel conveyance unit 300 will be describedlater. The control unit 400 has a function of reading out the slittingposition information 80 from the information storage medium 800 inaccordance with reading of the identification means or indicia 20 by anidentification means reading unit 120 which will be described later, andstoring the readout information in the storage device 420.

The optical film laminate feed unit 100 comprises a support rack 110adapted to be provided with the roll R of the continuous inspectedoptical film laminate in a rotatable manner, an identification meansreading unit 120 adapted to read the identification means or indicia 20,a first film feed unit 130 including a pair of feed rollers whichincorporate an encoder 131 adapted to measure a feed distance of thecontinuous inspected optical film laminate, a first speed adjustmentunit 140 including a dancer roller adapted to feed the continuousinspected optical film laminate at a constant speed, a slitting unit 150provided in the slitting station A to form a plurality of slits in thecontinuous inspected optical film laminate along a directionperpendicular to a feed direction of the continuous inspected opticalfilm laminate, based on distance measurement data obtained from the feeddistance of the continuous inspected optical film measured by theencoder 131 and the slitting position information 80 read out from theinformation storage medium 800 or the storage device 420, a slittingposition checkup unit 160 adapted to check a position of each of theslits formed in the slitting station A, a second film feed unit 170including a pair of feed rollers; a second speed adjustment unit 180including a dancer roller adapted to feed the continuous inspectedoptical film laminate at a constant speed, a defective polarizing sheetremoval unit 190 adapted, based on an instruction from the control unit400, to recognize the defective polarizing sheets and remove thedefective polarizing sheets from the continuous carrier film; alamination unit 200 provided in the lamination station B and including apair of lamination rollers adapted to peel the normal polarizing sheetseach cut into a give length corresponding to that of the liquid-crystalpanel, from the continuous carrier film, and then laminate the normalpolarizing sheets to respective ones of the liquid-crystal panels, acarrier film take up drive mechanism 210 adapted to take up thecontinuous carrier film, an edge detection unit 220 provided in thelamination station B to detect the leading edge of each of the normalpolarizing sheet, and a position or straight-ahead-posture detectionunit 230 adapted to detect a position or straight-ahead posture of eachof the normal polarizing sheets. Details of the liquid-crystal panelconveyance unit 300 will be described later, based on FIG. 13. FIG. 5 isa flowchart showing a manufacturing process performed by the abovecomponents of the system 1.

2. Production of Roll R of Continuous Inspected Optical Film Laminate

(Structure of Continuous Inspected Optical Film Laminate)

The roll R loaded in the support rack 110 of the optical film laminatefeed unit 100 is formed by winding a flexible, continuous inspectedoptical film laminate 10 which comprises a continuous polarizingcomposite film 11 including a continuous polarizer having a continuousprotective film laminated on at least one of opposite surfaces thereof,and an adhesive layer 12 applied to one side of the continuous polarizerto be laminated to a liquid-crystal panel, a continuous surfaceprotection film 13 having an adhesive surface laminated on thecontinuous polarizing composite film 11 at a surface opposite to theadhesive layer 12, and a continuous carrier film 14 releasably laminatedon the adhesive layer 12 of the continuous polarizing composite film 11,as shown in FIG. 2. A continuous polarizing composite film which has notbeen applied with the adhesive layer 12 (referred as “continuouspolarizing composite film on which the adhesive layer is not yet formed11′” or “continuous polarizing composite film 11′” to distinguish itfrom a continuous polarizing composite film 11 formed with the adhesivelayer 12, i.e., “continuous polarizing composite film including adhesivelayer 11”) or the continuous polarizing composite film includingadhesive layer 11 is preliminarily subjected to an inspection fordetermining the presence or absence of a defect contained therein, asshown in FIG. 3. In the process of producing the roll R of thecontinuous inspected optical film laminate 10, there are two inspectionmethods as described below.

One of the inspection techniques is designed to inspect a continuouspolarizing composite film on which the adhesive layer is not yet formed11′ during a process of laminating a continuous protective film on acontinuous polarizer formed from a PVA film to form the continuouspolarizing composite film on which the adhesive layer is not yet formed11′. The other inspection technique is designed to perform theinspection using a roll R′ of a continuous provisional optical filmlaminate 10′ which comprises a prepared continuous polarizing compositefilm 11 formed with an adhesive layer, and a continuous provisionalcarrier film 14 releasably laminated on the adhesive layer. Morespecifically. The other inspection technique is designed to peel thecontinuous provisional carrier film 14 from the continuous provisionaloptical film laminate 10′ being fed out from the roll R′ and inspect thecontinuous polarizing composite film including exposed adhesive layer11. Preferably, the continuous inspected optical film laminate 10 has awidth approximately equal to a long or short side of a liquid-crystalpanel to which the laminate 10 is to be attached. Preferably, thecontinuous protective film to be laminated on one or each of theopposite surfaces of the continuous polarizer is formed of a transparentprotective film. The continuous carrier film 14 is adapted, during aliquid-crystal display element manufacturing process, to protect theadhesive layer 12 of the continuous polarizing composite film 11, and,when a normal polarizing sheet is peeled from the continuous carrierfilm 14 and laminated to a liquid-crystal panel, it is separated fromthe polarizing sheet and taken up into a roll. The continuous carrierfilm 14 has a function of carrying a normal polarizing sheet cut into agiven length corresponding to that of a liquid-crystal panel, to thelamination station B. Therefore, it is referred to as “carrier film”herein.

For example, the continuous polarizing composite film on which theadhesive layer is not yet formed 11′ or the continuous polarizingcomposite film including adhesive layer 11 may be formed by thefollowing process. A PVA film having a thickness of about 50 to 80 μm issubjected to a dyeing treatment using iodine and a cross-linkingtreatment, and then subjected to an orientation treatment by a processof drawing in a lengthwise or widthwise direction thereof. As a result,an iodine complex is arranged in a direction parallel to the drawingdirection of the PVA film, so that a continuous polarizer having anabsorption axis in a direction parallel to the drawing direction isformed to absorb polarization in this direction. Preferably, the drawingdirection of the PVA film is aligned with the lengthwise or widthwisedirection of the PVA film to form a continuous polarizer havingexcellent uniformity, accuracy and optical characteristics. Typically,the absorption axis of a polarizer or a continuous polarizing compositefilm on which the adhesive layer is not yet formed 11′ including apolarizer therein is parallel to the longitudinal direction of thecontinuous polarizing composite film which the adhesive layer is not yetformed 11′, and a polarization axis thereof is a widthwise directionperpendicular to the longitudinal direction. The thickness of thepolarizer is in the range of 20 to 30 μm. Then, a continuous protectivefilm for protecting the formed continuous polarizing composite film islaminated on one or both of opposite surfaces of the continuouspolarizer through an adhesive layer. In many cases, a transparent TAC(triacetylcellulose) film having a thickness of about 40 to 80 μm isused for the continuous polarizing composite film. In order to reducethe thickness of a liquid-crystal display element, the continuousprotective film is laminated on only one of the surfaces of thecontinuous polarizer, in some cases. Finally, an acryl-based adhesivelayer is formed on one of opposite surfaces of the continuous protectivefilm-laminated continuous polarizer to form the adhesive layer-formedpolarizing composite film 11 for the purpose of attachment to a liquidcrystal panel. As shown in FIG. 2, the thickness of the adhesive layeris in the range of 10 to 30 μm. Typically, the thickness of thecontinuous polarizing composite film including adhesive layer 11 is inthe range of about 110 to 220 μm.

Typically, a PET (polyethylene terephthalate) film is used for each ofthe continuous surface protection film 13 and the continuous carrierfilm 14. Each of the continuous surface protection film 13 and thecontinuous carrier film 14 is a so-called “process material”, which ispeeled and removed before the final stage of the liquid-crystal displayelement manufacturing process. The continuous surface protection film 13is used to protect the continuous polarizing composite film 11 devoid ofthe adhesive layer so as not to be contaminated and damaged during theliquid-crystal display element manufacturing process, and the continuouscarrier film 14 is used to protect an exposed surface of the adhesivelayer. The continuous provisional carrier film 14′ may be of a typesimilar to the carrier film 14.

One of the protective films of continuous polarizing composite filmwhich the adhesive layer is not yet formed 11′ may be replaced with aphase difference film with a optical compensatory function, using acycloolefin-based polymer, a TAC-based polymer or the like. Thecontinuous polarizing composite film on which the adhesive layer is notyet formed 11′ may further be provided with a fixed layer by applyingand orienting a polymer material such as a polyester-based orpolyimide-based polymer material on a TAC-based transparent substrate.Further, in cases where the continuous polarizing composite film whichthe adhesive layer is not yet formed 11′ is used as a polarizingcomposite film to be laminated to the backlight side of a liquid-crystaldisplay element, a brightness enhancement film may laminated to acontinuous protective film on the backlight side of the liquid-crystaldisplay element to provide an additional function. Further, as for astructure of the continuous polarizing composite film on which theadhesive layer is not yet formed 11′, various variations, such aslaminating a TAC film to one of opposite surfaces of the continuouspolarizer and laminating a PET film to the other surface of thecontinuous polarizer, have been proposed.

One method for forming an adhesive layer for lamination to aliquid-crystal panel, on the continuous polarizing composite film onwhich the adhesive layer is not yet formed 11′ having the continuousprotective film laminated on one or both of the surfaces is to laminatea continuous carrier film 14 having an adhesive layer provided thereonin a transferable manner, to a surface of the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ to belaminated to the liquid-crystal panel. A specific transfer method willbe described below. In forming the continuous carrier film 14, thecontinuous carrier film 14 is subjected to a releasing treatment at thesurface which is to be laminated on the surface of the continuouspolarizing composite film on which the adhesive layer is not yet formed11′ which is to be laminated to a liquid-crystal panel, and a solventcontaining an adhesive is applied to the treated surface and dried toform an adhesive layer on the carrier film 14. Then, for example, thecontinuous carrier film 14 having the adhesive layer 12 is continuouslyfed and laminated to the continuous polarizing composite film on whichthe adhesive layer is not yet formed 11′ while synchronously feeding thecontinuous polarizing composite film on which the adhesive layer is notyet formed 11′, to transfer the adhesive layer of the continuous carrierfilm 14 to the continuous polarizing composite film 11′ to form anadhesive layer 12 thereon. Instead of the adhesive layer formed in theabove manner, an adhesive layer 12 may be formed by directly applying asolvent containing an adhesive to the surface of the continuouspolarizing composite film on which the adhesive layer is not yet formed11′ at a surface which is to be laminated to a liquid-crystal panel, anddrying the solvent.

Typically, the continuous surface protection film 13 has an adhesivesurface. Differently from the adhesive layer 12 of the continuouspolarizing composite film 11, when a surface protection sheet (notshown) is peeled from a continuous polarizing composite film includingadhesive layer 11″ during the liquid-crystal display elementmanufacturing process, the adhesive surface must be peeled together withthe surface protection sheet. FIG. 2 (product) shows a state after thesurface protection sheet is peeled and removed. The surface of thesurface protection film of the continuous polarizing composite film 11may be subjected to a hard coat treatment for protecting an outermostsurface of the liquid-crystal display element, and/or a surfacetreatment providing an anti-glare effect or the like, such as ananti-glare treatment, irrespective of whether the continuous surfaceprotection film 13 is laminated on the continuous polarizing compositefilm 11.

3. Production of Information Storage/Readout Device for Use in a Systemfor Continuously Manufacturing Liquid-Crystal Display Elements

With reference to FIGS. 6 to 9, description will be made on the methodand system for producing an information storage/readout device for usein the liquid-crystal display element manufacturing system, according tothe first and second embodiments of the present invention, wherein theinformation storage/readout device comprises an information storagemedium 800 which stores therein the slitting position information 80 forthe continuous inspected optical film laminate, and operates with a rollR of the continuous inspected optical film laminate 10 which is providedwith the identification means or indicia 20 associated with the slittingposition information 80.

(Method and System for Information Storage/Readout Device According toFirst Embodiment)

FIG. 6 is a schematic diagram showing a method and system for creatingthe slitting position information 80, and producing the roll R of thecontinuous inspected optical film laminate provided with theidentification means or indicia 20 associated with the slitting positioninformation 80 stored in the information storage medium 800. FIG. 7 is aflowchart showing the production process in the method and system forproducing the roll R, illustrated in FIG. 6.

According to the first embodiment illustrated in FIG. 6, there isprovided an information storage/readout device 500 which has a polarizermanufacturing line 510 for forming a continuous polarizer, a protectivefilm manufacturing line 520 for forming a continuous protective film tobe laminated on the continuous polarizer, a polarizing composite filmmanufacturing line 530 for laminating the continuous protective film onthe continuous polarizer through an adhesive to form the continuouspolarizing composite film which the adhesive layer is not yet formed11′, wherein the polarizing composite film manufacturing line includesan inspection station for performing an inspection for determining thepresence or absence of a defect contained in the continuous polarizingcomposite film which the adhesive layer is not yet formed 11′, anoptical film laminate manufacturing line 540 for releasably laminating acontinuous carrier film 14 formed with a transferable adhesive layer onone of the opposite surface of the continuous inspected polarizingcomposite film on which the adhesive layer is not yet formed 11′, andoptionally releasably laminating a continuous surface protection film 13on the other surface of the continuous inspected polarizing compositefilm 11′, to form the continuous inspected optical film laminate, andwherein the optical film laminate manufacturing line 540 includes anidentification providing station for providing the identification meansor indicia 20 on the continuous inspected optical film laminate, and aroll manufacturing line 550 for winding the continuous inspected opticalfilm laminate provided with the identification means or indicia 20 toform the roll R.

As shown in FIG. 6, the polarizer manufacturing line 510 includes astation provided with a rotatably loaded roll 51 of a PVA film servingas a substrate of a continuous polarizer, and designed to subject thePVA film to dyeing, cross-linking and drawing treatment and then todrying, while feeding the PVA film from the roll 51 by a laminationdrive mechanism 560 or other drive mechanism (not shown), to form acontinuous polarizer. The protective film manufacturing line 520includes a station provided with a rotatably loaded roll 52 of a filmwhich provides a substrate of the continuous protective film, typically,a transparent TAC film, and designed to subject the transparent TAC filmto a saponifying treatment and then to drying, while feeding thetransparent TAC film from the roll 52 by the lamination drive mechanism560 or other drive mechanism (not shown), to form a continuousprotective film. The polarizing composite film manufacturing line 530includes a station provided with the aforementioned lamination drivemechanism 560 having a pair of lamination rollers 561, 562, at adownstream side of the manufacturing lines 510, 520, and operates toapply an adhesive primarily consisting of a polyvinyl alcohol-basedresin to an interface between the polarizer and the protective film, anddrying the adhesive to bond them together through an adhesive layerhaving a thickness of only several μm by the lamination rollers, to forman continuous polarizing composite film on which the adhesive layer isnot yet formed 11′ (Step 1 in FIG. 7). The lamination drive mechanism560 comprises a length measurement device having an encoder 570incorporated in one of the lamination rollers to obtain distancemeasurement data based on a feed distance of the leading edge of thecontinuous polarizing composite film which the adhesive layer is not yetformed 11′ just after being formed. Based on the length measurementdevice having the encoder 570 incorporated therein, the feed distance ofthe continuous polarizing composite film 11′ can be measured. Thelamination rollers 561, 562 are adapted to laminate the continuouspolarizer and the continuous protective film to each other in a pressbonding manner to form the continuous polarizing composite film 11′. Thelamination rollers 561, 562 are also adapted to continuously feed thecontinuous polarizing composite film which the adhesive layer is not yetformed 11′ in an inter-related manner with an optical film laminate takeup drive mechanism 630 which will be described later.

As shown in FIG. 6 and Step 3 in FIG. 7, the polarizing composite filmmanufacturing line 530 further includes an inspection station M forinspecting a surface and inside of the continuous polarizing compositefilm which the adhesive layer is not yet formed 11′ to detect any defectexisting in the continuous polarizing composite film on which theadhesive layer is not yet formed 11′. The inspection station M comprisesan inspection unit 580. For example, the inspection unit 580 is adaptedto perform reflection inspection, transmission inspection, and/orcross-Nicol transmission inspection, as will be described later. In theinspection station M, based on the position of the detected defect inthe continuous polarizing composite film which the adhesive layer is notyet formed 11′, a control unit 700 associated with the inspection unit580 operates to calculate and store a defect-free, normal region Xα anda defect-containing, defective region Xβ each delimited in a directionperpendicular to a longitudinal direction of the continuous polarizingcomposite film which the adhesive layer is not yet formed 11′, by usingan information processing device 710 and a storage device 720 (Steps 4to 6 in FIG. 7). The control unit 700 further operates to createslitting position information which indicates normal-polarizing-sheetslitting positions defining a normal or defect-free polarizing sheet Xαcorresponding to the normal region Xα, and defective-polarizing-sheetslitting positions defining a defective or defect-containing polarizingsheet Xβ corresponding to the defective region Xβ. Thus, the slittingposition information 80 is provided in the continuous inspected opticalfilm laminate which is then finally formed into the roll R (Step 7 inFIG. 7). Then, the control unit 700 operates to store the slittingposition information in the storage device 720, and then store theslitting position information in the information storage medium 800. Inorder to backup the slitting position information 80, the slittingposition information 80 may be stored in a plurality of informationstorage media 800. The control unit 700 may be configured to, aftercreating the slitting position information 80, directly transfer theslitting position information 80 to the storage device 420 of thecontinuous manufacturing system for liquid-crystal display element 1 viathe Internet or a dedicated line, without involving the informationstorage medium 800. In this case, the storage device 420 functions as“information storage medium” in accordance with the present invention.

The relation between the inspection unit 580 and the control unit 700will be described below. The inspection unit 560 comprises an imagereading unit 581 such as a CCD camera. The image reading unit 581 iselectrically connected to the information processing device 710 of thecontrol unit 700. The information processing device 710 operates toprocess image data read by the image reading unit 581, in associationwith the distance measurement data obtained by the length measurementdevice having the encoder 570 which is electrically connected to theinformation processing device 710. The control unit 700 operates tocause the information processing device 710 and the storage device 720to process the image data from the image reading unit 581 in associationwith the distance measurement data obtained by the length measurementdevice having the encoder 570 based on the feed distance of thecontinuous polarizing composite film on which the adhesive layer is notyet formed 11′ (typically, a leading edge thereof) from an inspectionposition, to create position data indicative of the position of a defectcontained in the continuous polarizing composite film 11′, and thenstore the position information in the storage device 720 (Step 5 in FIG.7). Then, the control unit 700 firstly operates to determine a normalregion Xα and a defective region Xβ in the continuous polarizingcomposite film 11′, based on the position data about the defect position(Step 6 in FIG. 7). As described in detail later, based on the normalregion Xα and the defective region Xβ determined in the continuouspolarizing composite film 11′, the control unit 700 operates to createslitting position information 80 which indicates normal-polarizing-sheetslitting positions and defective-polarizing-sheet slitting positionseach consisting of a downstream side slitting position and an adjacentand upstream side slitting position to define respective ones of anormal polarizing sheet Xα and a defective polarizing sheet Xβ, in thecontinuous inspected optical film laminate which is finally formed intothe roll R to be used by the optical film laminate feed unit 100 in FIG.4.

Then, the control unit 700 operates to store the slitting positioninformation 80 in the storage device 720 (Step 7 in FIG. 7). Theslitting information 80 is information indicative of positions whereslits are to be formed in the continuous inspected optical film laminatealong the direction perpendicular to the feed direction thereof. Asdescribed in detailed later, based on the slitting position information80, when the continuous inspected optical film laminate is fed out fromthe roll R installed in the continuous manufacturing system forliquid-crystal display element (FIG. 4), in the slitting station A, aplurality of slits are formed in the continuous inspected optical filmlaminate along a direction perpendicular to a longitudinal direction ofthe continuous inspected optical film laminate from a surface oppositeto the continuous carrier film to a depth reaching a surface of thecontinuous carrier film adjacent to the adhesive layer, to form apolarizing sheet 11″ having the adhesive layer applied thereto, as shownin FIG. 2 (product). Then, the control unit 700 operates to store theslitting position information 80 in the information storage medium 800via the storage device 720 (Step 16 in FIG. 7). In order to back up theslitting position information 80, the slitting position information 80may be stored in a plurality of the information storage media 800. Theidentification means or indicia 20 created for reading out the slittingposition information 80 from the information storage medium 800 or thestorage device 420 is provided on the continuous inspected optical filmlaminate which is finally formed into the roll R (Step 14 in FIG. 7).Thus, the continuous inspected optical film laminate 10 provided withthe identification means or indicia 20 is formed (Step 15 in FIG. 7).The identification means or indicia 20 may include information, such asmanufacturing lot, a length (m) of the roll, or the like, associatedwith the slitting position information 80. Preferably, theidentification means or indicia 20 is provided on the continuousinspected optical film laminate 10 at a position corresponding to astart position of the defect inspection for the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′.

Meanwhile, a polarizing sheet 11″ formed by adjacent two slits is anormal polarizing sheet Xα having a given length determined by thelength of a long or short side the liquid-crystal panel to which thesheet is to be attached, or a defective polarizing sheet Xβ having alength, typically, less than the given length xα. As shown in FIG. 4,during the liquid-crystal display element continuous manufacturingprocess, the control unit 400 operates to cause the identificationreading unit 120 to read the identification means or indicia 20 of thecontinuous inspected optical film laminate 10, and to read out theslitting position information 80 from the information storage medium 800or the storage device 420 based on the read identification means orindicia 20. Then, the control unit 400 operates to cause the slittingunit 150 to form adjacent two slits in the continuous inspected opticalfilm laminate so as to cut a defective polarizing sheet Xβ, based on theslitting position information 80 read out from the information storagemedium 800 or the storage device 420 in accordance with the results ofreading of the identification means or indicia 20. Then, the controlunit 400 operates to cause the defective polarizing sheet removal unit190 in the removal station C to remove the defective polarizing sheet Xβfrom the continuous carrier film 14. The control unit 400 also operatesto cause the slitting unit 150 to form adjacent two slits to cut anormal polarizing sheet Xα of the given length corresponding to that ofthe liquid-crystal panel, and to cause the lamination unit 200 in thelamination station B to peel the normal polarizing sheet Xα from thecontinuous carrier film 14 and laminate the peeled normal polarizingsheet Xα to one side of the liquid-crystal panel.

Thus, the length xα of a normal polarizing sheet determined by theposition data of a defect existing in the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ is setto a constant value determined by a length of a side of theliquid-crystal panel to which the sheet is to be attached, in any case.Differently, the length xβ of a defective polarizing sheet is determinedby a downstream side slit and an upstream side slit. The upstream sideslit is formed slightly upstream of the position of a defect, and theupstream side slit of an immediately preceding normal polarizing sheetmay be used as the downstream side slit of the succeeding defectivepolarizing sheet, when viewed in the feed direction. The distancebetween the downstream side slit and the defect position varies whenviewed in the feed direction, and thereby the length xβ of a defectivepolarizing sheet also varies. As described in detail later, preferably,the processing for the slitting position information 80 indicative ofslitting positions is configured to allow the length xβ of the defectivepolarizing sheet to be set to a value different from the length xα of anormal polarizing sheet, for example, to a value satisfying the relationxβ<xα, in any case. However, if the length xα of a normal polarizingsheet is equal to the length xβ of the defective polarizing sheet,defective sheet-identification information Xγ has to be used todistinguish a normal polarizing sheet from a defective polarizing sheet.It will not be necessary to specifically mention that the defectivesheet-identification information Xγ is stored in the information storagemedium 800 together with the slitting position information 80 inassociation with the slitting position information 80. In the system 1illustrated in FIG. 4, during the liquid-crystal display elementmanufacturing process, according to the slitting position informationread out from the information storage medium 800 or the storage device420, the slitting unit 150 in the slitting station A operates to form anormal polarizing sheet Xα and a defective polarizing sheet Xβ, and thedefective polarizing sheet removal unit 190 in the removal station Coperates to recognize and remove the defective polarizing sheet Xβ. Incases where the defective sheet-identification information Xγ is storedin the information storage medium 800 by being associated with theslitting position, the defective polarizing sheet removal unit 190operates to recognize only the defective polarizing sheet Xβ based onthe defective sheet-identification information Xγ, and remove thedefective sheet Xβ. The process of creating the slitting positioninformation is common to the first and second embodiments, and thereforewill be described later, based on FIGS. 16 to 22.

After completion of the defect inspection for the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′, it isnecessary to form an adhesive layer 12 for lamination to theliquid-crystal panel, on one of the opposite surfaces of the continuouspolarizing composite film on which the adhesive layer is not yet formed11′. As shown in FIG. 6, the optical film laminate manufacturing line540 includes a carrier film feed unit 590 provided with a roll 59 of acontinuous carrier film 14 having an adhesive layer formed thereon in atransferable manner. The continuous carrier film 14 is preliminarilyformed in a carrier film manufacturing line (not shown), using a PET(polyethylene terephthalate) film having a thickness of about 20 to 50μm, as a substrate. Typically, one surface of the PET film is subjectedto a releasing treatment, and then a solvent containing an acryl-basedadhesive is applied to the treated surface and dried to form atransferable adhesive layer having a thickness of 10 to 30 μm, on onesurface of the continuous carrier film 14. Then, a releasable film isreleasably laminated on the adhesive layer. The continuous carrier film14 is fed from the carrier film feed unit 590 while peeling off thereleasable film, and releasably laminated on the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ by apair of carrier film lamination rollers 591, 592. Through thisoperation, the adhesive layer formed on the continuous carrier film 14is transferred to the continuous polarizing composite film 11′ to form acontinuous polarizing composite film including adhesive layer 11.

The optical film laminate manufacturing line 540 may include a surfaceprotection film feed unit 640 for laminating a continuous surfaceprotection film 13 having an adhesive surface, on the continuouspolarizing composite film including adhesive layer 11 at a surfaceopposite to the continuous carrier film laminated thereon. The opticalfilm laminate manufacturing line 540 further includes an identificationproviding unit 620 for, after forming the continuous inspected opticalfilm laminate 10 by laminating the continuous surface protection film 13and/or the continuous carrier film 14 on the continuous polarizingcomposite film including adhesive layer 11, providing the identificationmeans or indicia 20 at a position corresponding to the position wherethe defect inspection is started on the continuous polarizing compositefilm which the adhesive layer is not yet formed 11′. The identificationmeans or indicia 20 is created in association with the slitting positioninformation 80 stored in the information storage medium 800. In thecontinuous manufacturing system for liquid-crystal display element 1(FIG. 4) provided with the roll R of the continuous inspected opticalfilm laminate 10 which has the identification means or indicia 20provided thereon, the identification means or indicia 20 serves as meansto allow the slitting position information 80 to be read out from theinformation storage medium 800 or the storage device 420, in accordancewith the results of reading thereof from the continuous inspectedoptical film laminate 10 by the identification means reading unit 120.

The roll manufacturing line 550 includes an optical film laminate takeup drive mechanism 630 having a pair of winding rollers 631, 632adapted, after the identification means or indicia 20 is provided on thecontinuous inspected optical film laminate 10 by the providing unit 620,to wind the continuous inspected optical film laminate 10 to produce theroll R (Step 15 in FIG. 7). In cases where the continuous protectivefilm is laminated on each of the surfaces of the continuous polarizer,the system 500 includes two protective film manufacturing lines 520,520′ (in this embodiment, the protective film manufacturing line 520′ isomitted). Further, a treatment line may be added to the protective filmmanufacturing line 520 to subject a surface (non-lamination surface) ofthe continuous protective film to a hard coat treatment or an antidazzleor anti-glare treatment, before the continuous protective film islaminated on the continuous polarizer.

(Method and System for Producing Information Storage/Readout DeviceAccording to Second Embodiment)

FIG. 8 is a schematic diagram showing a method and system for creatingthe slitting position information 80, and producing the roll R of thecontinuous inspected optical film laminate provided with theidentification means or indicia 20 associated with the slitting positioninformation 80 stored in the information storage medium 800, using aroll R′ of a continuous provisional optical film laminate R′. FIG. 9 isa flowchart showing the production process in the method and system forproducing the roll R, illustrated in FIG. 8.

An information storage/readout device 500′ according to the secondembodiment illustrated in FIG. 8 will be described by designating partswith identical reference characters to those in the system 500 accordingto the first embodiment except those different from the parts in thesystem 500. In the system 500′ according to the second embodiment, aroll R′ of a preliminarily produced and prepared continuous provisionaloptical film laminate 10′ is used. The roll R′ is formed by winding thecontinuous provisional optical film laminate 10′ comprising a continuouspolarizing composite film 11 with an adhesive layer and a continuousprovisional carrier film 14′ releasably laminated on the adhesive layer,into a roll. The continuous polarizing composite film 11 in thecontinuous provisional optical film laminate 10′ consists of acontinuous polarizing composite film before a defect inspection, i.e.,before detecting a defect contained therein, and includes an adhesivelayer and a continuous provisional carrier film 14′ releasably laminatedon the adhesive layer to protect the adhesive layer. Thus, the system500′ according to the second embodiment comprises a provisional opticalfilm laminate feed line 510′ for feeding the continuous provisionaloptical film laminate 10′ from the roll R′, and a polarizing compositefilm feed line 520′ for peeling the continuous provisional carrier film14′ from the continuous provisional optical film laminate 10′, andfeeding the continuous polarizing composite film including adhesivelayer 11 in an exposed state.

One feature of the system 500′ according to the second embodiment is tosubject the continuous polarizing composite film including exposedadhesive layer 11 to the defect inspection, differently from the system500 according to the first embodiment where the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ itselfis subjected to the defect inspection. While the two systems 500, 500′have a difference in whether or not the continuous polarizing compositefilm to be subjected to the defect inspection has an adhesive layer,each of the systems has a polarizing composite film manufacturing line(530, 530′) for inspecting a defect contained in the continuouspolarizing composite film, and an optical film laminate manufacturingline (540, 540′) for releasably laminating a continuous surfaceprotection film 13 and/or a continuous carrier film 14. In thepolarizing composite film manufacturing line 530′ in the secondembodiment, image data of the continuous polarizing composite filmincluding adhesive layer 11 to be laminated to a liquid-crystal panel isread by an image reading unit 581 such as a CCD camera. As in the system500 according to the first embodiment, the image reading unit 581 iselectrically connected to an information processing device 710 of acontrol unit 700. In the information processing device, the image dataread by the image reading unit 581 is processed in association withdistance measurement data obtained by a length measurement device havingan incorporated encoder 570′ electrically connected to the informationprocessing device 710.

The optical film laminate manufacturing line 540′ in the secondembodiment includes a carrier film feed unit 590′ provided with a roll59′ of a continuous carrier film 14 which has a surface subjected to areleasing treatment so that it can be releasably laminated on theexposed adhesive layer of the continuous polarizing composite filmincluding adhesive layer 11. The continuous carrier film 14 ispreliminarily formed in a carrier film manufacturing line (not shown),using a PET (polyethylene terephthalate) film having a thickness ofabout 20 to 50 μm, as a substrate. In the second embodiment, there is noneed for a releasable film, because one surface of the PET film in thecontinuous carrier film 14 is subjected to a releasing treatment withoutforming a transferable adhesive layer as in the first embodiment. Thecontinuous carrier film 14 is fed from the carrier film feed unit 590′,and releasably laminated on the adhesive layer of the continuouspolarizing composite film 11 by a pair of carrier film laminationrollers 591′, 592′. The roll manufacturing line 550 of the system 500′according to the second embodiment has the same configuration andfunction as those of the roll manufacturing line 550 of the system 500according to the first embodiment, and its description will be omitted.

Another feature of the system 500′ according to the second embodiment isto use the roll R′ of the preliminarily formed continuous provisionaloptical film laminate 10′. Thus, it is understood that the system 500′is devoid of the polarizing composite film manufacturing line and theprotective film manufacturing line in the first embodiment. Further,there is no need for a station for applying an adhesive to the interfacebetween the continuous polarizer and the continuous protective film, anddrying the adhesive to bond them together using the pair of laminationrollers 561, 562 of the lamination drive mechanism 560 as in thepolarizing composite film manufacturing line 530 in the firstembodiment. Such a station corresponds to the provisional optical filmlaminate feed line 510′ illustrated in FIG. 8 (Step 1 in FIG. 9). Theprovisional optical film laminate feed line 510′ comprises a provisionaloptical film laminate feed drive mechanism 560′ including a pair of feedrollers 561′, 562′ adapted to feed the continuous provisional opticalfilm laminate 10′ from the roll R′ loaded in a support rack. Theprovisional optical film laminate feed drive mechanism 560′ comprises alength measurement device having the encoder 570′ incorporated in one ofthe lamination rollers and adapted to measure the feed distance of theleading edge of the continuous provisional optical film laminate 10′ andcreate distance measurement data. Based on the length measurement devicehaving an incorporated encoder 570′, the feed distance of the continuousprovisional optical film laminate 10′ can be measured (Step 2 in FIG.9). The feed rollers 561′, 562′ are adapted to continuously feed thecontinuous provisional optical film laminate 10′ in inter-related mannerwith an optical film laminate take up drive mechanism 630 for winding acontinuous inspected optical film laminate 10 to produce the roll R.

The provisional optical film laminate feed line 510′ illustrated in FIG.8 operates to feed the continuous provisional optical film laminate 10′including the continuous provisional carrier film 14′, to a provisionalcarrier film peeling station L by the provisional optical film laminatefeed drive mechanism 560′. In the provisional carrier film peelingstation L of the polarizing composite film feed line 520′, thecontinuous provisional carrier film 14′ is peeled from the continuousprovisional optical film laminate 10′ to form an continuous polarizingcomposite film 11, and the continuous polarizing composite film 11 isfed with the adhesive layer in an exposed state (Steps 3 and 4 in FIG.9). A polarizing composite film manufacturing line 530′ operates to feedthe continuous polarizing composite film 11 with the adhesive layer inthe exposed state to an inspection station M for detecting a defectcontained in the continuous polarizing composite film including exposedadhesive layer 11. In the information storage/readout device system 500according to the second embodiment, a process of producing thecontinuous inspected optical film laminate 10 is substantially initiatedat the polarizing composite film manufacturing line 530′.

Preferably, the roll R′ of the continuous provisional optical filmlaminate 10′ is preliminarily formed using a continuous provisionalcarrier film 14′ formed with a transferable adhesive layer. This makesit possible to transfer the transferable adhesive layer on thecontinuous provisional carrier film 14′ to the continuous polarizingcomposite film when the continuous provisional optical film laminate 10′is fed out from the roll R′, and the continuous provisional carrier film14′ is peeled from the continuous provisional optical film laminate 10′in the system 500′ according to the second embodiment, to form acontinuous polarizing composite film including adhesive layer 11. Exceptthat the continuous polarizing composite film 11 is subjected to thedefect inspection with the adhesive layer provided thereon, theinspection station M of the polarizing composite film manufacturing line530′ is the same as the inspection station M of the polarizing compositefilm manufacturing line 530 in the first embodiment. The inspectionstation M comprises an inspection unit 580. For example, the inspectionunit 580 is adapted to perform reflection inspection, transmissioninspection, and/or cross-Nicol transmission inspection, as will bedescribed later. In the inspection station M, there is provided acontrol unit 700 associated with the inspection unit 580 which operates,based on the position of the detected defect in the continuouspolarizing composite film including adhesive layer 11, to conductcalculations to determine a defect-free, normal region Xα and adefect-containing, defective region Xβ each being defined in a directionperpendicular to the longitudinal direction of the continuous polarizingcomposite film including adhesive layer 11, by using the informationprocessing device 710. There is further provided a storage device 720for storing the results of calculations (Steps 5 to 8 in FIG. 9). Thecontrol unit 700 further operates to create slitting positioninformation which indicates normal-polarizing-sheet slitting positionsdefining a normal or defect-free polarizing sheet Xα corresponding tothe normal region Xα, and defective-polarizing-sheet slitting positionsdefining a defective or defect-containing polarizing sheet Xβcorresponding to the defective region Xβ, and finally serves as theslitting position information 80 for the continuous inspected opticalfilm laminate finally formed into the roll R (Step 9 in FIG. 9). Then,the control unit 700 operates to store the slitting position information80 in an information storage medium 800 via the storage device 720 (Step18 in FIG. 9). In order to back up the slitting position information 80,the slitting position information 80 may be stored in a plurality ofinformation storage media 800.

The relation between the inspection unit 580 and the control unit 700 isthe same as that in the system 500 according to the first embodiment.The information processing device 710 operates to process image dataread by the image reading unit 581, in association with distancemeasurement data obtained by the length measurement device having theencoder 570′ electrically connected to the information processing device710. The control unit 700 operates to cause the information processingdevice 710 and the storage device 720 to process the image data from theimage reading unit 581 in association with the distance measurement dataobtained by the length measurement device having the encoder 570′ basedon the feed distance of the continuous provisional optical film laminate10′ (typically, the leading edge thereof) from a position where itpasses through the provisional optical film laminate feed drivemechanism 560′, to create position data indicative of the position of adefect contained in the continuous polarizing composite film includingadhesive layer 11′ (Step 6 in FIG. 9)., and then store the positioninformation in the storage device 720 (Step 7 in FIG. 9). Then, thecontrol unit 700 firstly operates to define a defect-free, normal regionXα and a defect-containing, defective region Xβ in the continuouspolarizing composite film 11, based on the position data on the defectposition (Step 8 in FIG. 9). As described in detail later, based on thenormal region Xα and the defective region Xβ defined in the continuouspolarizing composite film 11, the control unit 700 operates to createslitting position information 80 which indicates normal-polarizing-sheetslitting positions and defective-polarizing-sheet slitting positionseach consisting of a downstream-side slitting position and an adjacentand upstream side slitting position to determine respective ones of anormal polarizing sheet Xα and a defective polarizing sheet Xβ, in thecontinuous inspected optical film laminate which is to be finally formedinto the roll R for use with the optical film laminate feed unit 100 inFIG. 4.

Then, the control unit 700 operates to store the slitting positioninformation 80 in the storage device 720 (Step 9 in FIG. 9). As in thefirst embodiment, the slitting information 80 includes informationindicative of the position where a slit is to be formed in thecontinuous inspected optical film laminate finally formed into the rollR and being fed out from the roll R, along a direction perpendicular tothe feed direction thereof. Based on the slitting position information80, when the continuous inspected optical film laminate is fed out fromthe roll R installed in the continuous manufacturing system forliquid-crystal display element (FIG. 4), in the slitting station A, aplurality of slits are formed in the continuous inspected optical filmlaminate along a direction perpendicular to the longitudinal directionof the continuous inspected optical film laminate from a surfaceopposite to the continuous carrier film to a depth reaching a surface ofthe continuous carrier film adjacent to the adhesive layer, to form apolarizing sheet 11″ with the adhesive layer, as shown in FIG. 2(product). Then, the control unit 700 operates to store the slittingposition information 80 in the information storage medium 800 via thestorage device 720 (Step 18 in FIG. 9). The identification means orindicia 20 is provided on the continuous inspected optical film laminateto allow the slitting position information 80 to be retrieved from theinformation storage medium 800 or the storage device 420 (Step 16 inFIG. 9). Thus, the continuous inspected optical film laminate 10provided with the identification means or indicia 20 is formed (Step 17in FIG. 9). Preferably, the identification means or indicia 20 isprovided on the continuous inspected optical film laminate 10 at aposition corresponding to the position where the defect inspection isstarted on the continuous polarizing composite film including adhesivelayer 11. The identification means or indicia 20 may includeinformation, such as manufacturing lot, a length (m) of the roll, or thelike, associated with the slitting position information 80. Meanwhile, apolarizing sheet 11″ defined between adjacent two slits is a normalpolarizing sheet Xα having a given length determined by the length of along or short side of the liquid-crystal panel, or a defectivepolarizing sheet Xβ having a length, typically, less than the givenlength xα, as in the case of the first embodiment.

4. System for Continuously Manufacturing Liquid-Crystal Display ElementsUsing Information Storage/Readout Device

(Feeding Continuous Inspected Optical Film Laminate Provided withIdentification Means or Indicia)

FIG. 10 is a schematic diagram showing the relationship between theidentification means or indicia 20 read by the identification readingunit 120 and the slitting position information 80 read out from theinformation storage medium 800 or the storage device 420 in accordancewith the identification means or indicia 20, in the system forcontinuously manufacturing liquid-crystal display element illustrated inFIG. 4, using an information storage/readout device according to oneembodiment of the present invention, which comprises the informationstorage medium 800 storing therein the slitting position information 80created for the continuous inspected optical film laminate 10 by theproduction system for the roll R, illustrated in FIG. 6 or 8, and theroll R of the continuous inspected optical film laminate 10 providedwith the identification means or indicia 20 associated with the slittingposition information 80. As a third embodiment of the present invention,a method and system for continuously manufacturing liquid-crystaldisplay elements, using the information storage/readout device, will bedescribed with reference to the flowchart in FIG. 5.

(Recognition of Slitting Position)

In the third embodiment, the roll R of the continuous inspected opticalfilm laminate 10 provided with the identification means or indicia 20 isrotably loaded in the support rack of the optical film laminate feedunit 100 of the continuous manufacturing system for liquid-crystaldisplay element, and the continuous inspected optical film laminate 10provided with the identification means or indicia 20 (hereinafterreferred to simply as “continuous inspected optical film laminate 10”)is continuously fed out from the roll R (Step 1 in FIG. 5). During thefeeding, in Step 2 illustrated in FIG. 5, the identification means orindicia 20 provided on the continuous inspected optical film laminate 10is read, and the slitting position information 80 is read out from theinformation storage medium 800 or the storage device 420 in accordancewith reading of the identification means or indicia 20, and stored inthe storage device 420. Further, in the information processing device410, the read-out slitting position information is associated withdistance measurement data about the feed distance of the continuousinspected optical film laminate 10 measured by the encoder 131illustrated in FIG. 4, to determine normal-polarizing-sheet slittingpositions defining a normal polarizing sheet Xα anddefective-polarizing-sheet slitting positions defining a defectivepolarizing sheet Xβ, in Step 2 illustrated in FIG. 5. In Step 5illustrated in FIG. 5, the slitting positions are sequentially acquiredby the optical film laminate feed unit 100 illustrated in FIG. 4 for thecontinuous inspected optical film laminate 10.

As shown in FIG. 4, the control unit 400 operates to cause the firstfilm feed unit 130 including the pair of feed rollers to feed thecontinuous inspected optical film laminate 10, based on the slittingposition information and the distance measurement data about the feeddistance, and then to cause the first speed adjustment unit 140 totemporarily stop the feeding of the continuous inspected optical filmlaminate 10 (Step 7 in FIG. 5). Then, the control unit 400 operates tocause the slitting unit 150 in the slitting station A to, based on thesequentially acquired slitting positions, form a plurality of slits inthe continuous inspected optical film laminate 10 from a surfaceopposite to the continuous carrier film 14 to a depth reaching a surfaceof the continuous carrier film adjacent to the adhesive layer.Respective positions of the slits formed in the continuous inspectedoptical film laminate 10 are checked by the slitting position checkupunit 160 (Step 8 in FIG. 5). Then, in the removal station C, the normalpolarizing sheet Xα and the defective polarizing sheet Xβ cut on thecontinuous carrier film 14 of the continuous inspected optical filmlaminate 10 are identified or discriminated in terms of a difference inlength, and only the defective polarizing sheet Xβ is peeled and removedfrom the continuous carrier film 14, by the defective polarizing sheetremoval unit 190 operated in inter-related manner with the second speedadjustment unit 180 and the second film feed unit 170 including the pairof feed rollers (Step 9 in FIG. 5). In cases where the continuousinspected optical film laminate 10 has the defectivesheet-identification information Xγ associated with the slittingposition information, the defective polarizing sheet removal unit 190operates to peel and remove only the defective polarizing sheet Xβ fromthe continuous carrier film 14 based on the defectivesheet-identification information Xγ. The continuous inspected opticalfilm laminate 10 after removal of the defective polarizing sheet Xβ isfed to the lamination station B by the carrier film take up drivemechanism 210 in synchronization with each of a plurality ofliquid-crystal panels W being sequentially conveyed to the laminationstation B. The continuous carrier film 14 is taken up at a positionwhere the leading edge of the normal polarizing sheet Xα cut into agiven length corresponding to the liquid-crystal panel W reaches theleading edge of a corresponding one of the liquid-crystal panels W beingsequentially conveyed (Step 11 in FIG. 5) to allow the normal polarizingsheet Xα to be peeled from the continuous carrier film 14, and anoperation of laminating the normal polarizing sheet Xα to theliquid-crystal panel W by the lamination unit 200 including the pair oflamination rollers is initiated.

The operation of each of the devices, units and mechanisms under controlby the control unit 400 in the liquid-crystal display panelmanufacturing process will be more specifically described together withthe operation of laminating the normal polarizing sheet Xα to theliquid-crystal panel W.

(Removal of Defective Polarizing Sheet Xβ)

Under a condition wherein, in the continuous inspected optical filmlaminate 10, the normal polarizing sheet Xα and the defective polarizingsheet Xβ are cut along the slits and releasably retained on thecontinuous carrier film 14, the defective polarizing sheet removal unit190 operates, under control of the control unit 400, to identify ordiscriminate only the defective polarizing sheet X having a lengthdifferent from that of the normal polarizing sheet Xβ, or only thedefective polarizing sheet Xβ associated with the defectivesheet-identification information Xγ, and then peel and remove theidentified defective polarizing sheet Xβ from the continuous carrierfilm 14. FIGS. 11(1) and 11(2) show a specific example of the defectivepolarizing sheet removal units 190 which is operable, under the controlof the control unit 400, to identify or discriminate only the defectivepolarizing sheet Xβ.

A defective polarizing sheet removal unit 190 in FIG. 11(1) comprises adummy film drive mechanism 191 having a function of allowing thedefective polarizing sheet Xβ on the continuous carrier film 14 to beadhered thereto and peeled from the continuous carrier film 14, and ashifting mechanism 192 adapted, when the defective polarizing sheet Xβreaches the start position of removal of the defective polarizing sheetXβ in a feed path of the continuous inspected optical film laminate 10,to shift the feed path of the continuous inspected optical film laminate10 in such a manner that it comes close to and moves away from a dummyfilm feed path of the dummy film drive mechanism 191.

In FIG. 11(2), there is shown a defective polarizing sheet removal unit190 which is adapted, under control of the control unit 400, to be movedin an inter-related manner with the lamination unit 200 including thepair of lamination rollers, and comprises a dummy film drive mechanism191 having a function of feeding a dummy film in such a manner that thedefective polarizing sheet Xβ is adhered to the dummy film and peeledfrom the continuous carrier film 14, and a movable roller 192 defining adummy film feed path of the dummy film drive mechanism 191. Thedefective polarizing sheet removal unit 190 in FIG. 11(2) is differentfrom the defective polarizing sheet removal unit 190 in FIG. 11(1) inthat the movable roller 192 defining the dummy film feed path of thedummy film drive mechanism 191 is disposed adjacent to the pair oflamination rollers of the lamination unit 200, and adapted to be movedto a position where it is paired with one of the lamination rollers.Specifically, in the lamination station B, when the defective polarizingsheet Xβ reaches an end of the feed path of the continuous inspectedoptical film laminate 10 (i.e., the start position of removal of thedefective polarizing sheet Xβ), the control unit 400 operates to movethe lamination rollers apart from each other, and move the movableroller 192 defining the dummy film feed path to a gap between thelamination rollers located in spaced-apart relation, so that the movableroller is paired with one of the other lamination rollers. At thistiming, the continuous carrier film 14 is taken up by the carrier filmtake up drive mechanism 210, and the defective polarizing sheet Xβ ispeeled from the continuous carrier film 14, so that the peeled defectivepolarizing sheet Xβ is adhered to the dummy film in the dummy film feedpath by the movable roller 192 paired with the one lamination roller,and removed.

(Checkup of Slitting Position for the Continuous Optical Film Laminate)

In the production process of the roll R of the continuous inspectedoptical film laminate 10, the slitting positions (positions where slitsare to be formed in the continuous inspected optical film laminate 10)are determined by the slitting position information 80 created based onthe detected defect position in the continuous polarizing composite filmon which the adhesive layer is not yet formed 11′ or the continuouspolarizing composite film including adhesive layer 11 to indicate thedefective polarizing sheet-slitting position and the normal polarizingsheet-slitting position defining respective ones of the defectivepolarizing sheet Xβ and the defective polarizing sheet Xβ, and thedistance measurement data about the feed distance of the continuousinspected optical film laminate 10. Then, during the liquid-crystaldisplay element manufacturing process, the slitting positions aresequentially acquired by the slitting unit 150 according to aninstruction of the control unit 400. Based on the slitting positions,the slitting unit 150 in the slitting station A sequentially forms aplurality of slits in the continuous inspected optical film laminate 10along a direction perpendicular to the feed direction thereof. Theslitting unit 150 operates according to an instruction of the controlunit 400. If a slit formed by the slitting unit 150 based on theinstruction is misaligned with the slitting positions defined by theslitting position information 80 associated with the distancemeasurement data of the continuous inspected optical film laminate 10,the operation of the control unit 400 for having the slitting unit 150acquire the slitting position information 80 from the slitting unit 150may become meaningless.

FIG. 12 is a schematic diagram showing the operation of a slittingposition checkup unit 160 for checking a position of a slit formed inthe continuous inspected optical film laminate 10 fed out from theroller R in the continuous manufacturing system, based on the distancemeasurement data about the feed distance of the continuous inspectedoptical film laminate 10, and the slitting position information read outby reading the identification means or indicia 20 provided on thecontinuous inspected optical film laminate 10. The slitting positioncheckup unit 160 is provided on each of upstream and downstream sides ofthe slitting unit 15 when viewed in the feed direction of the continuousinspected optical film laminate 10. There is provided a film feed unit170 including a pair of feed rollers downstream of the downstreamslitting position checkup unit 160 which functions to temporarily stopthe feeding of the continuous inspected optical film laminate 10 duringthe period when slits are being formed therein and restart the feedingafter the slits are formed. The first speed adjustment unit 140including the dancer roll is disposed upstream of the upstream slittingposition checkup unit 160 to maintain the feeding of the continuousinspected optical film laminate 10 by the first film feed unit 130including the pair of feed rollers, even if the feeding of thecontinuous inspected optical film laminate 10 is temporarily stoppedwhen slits are formed therein.

A checkup can be performed as to whether the position of a slit formedalong a direction perpendicular to the feed direction of the continuousinspected optical film laminate 10 is aligned with the slitting positionbased on the slitting position information 80 and the distancemeasurement data about the feed distance of the continuous inspectedoptical film laminate 10 by determining accurate positions in the feed(traveling) direction (X-direction) and a crosswise direction(Y-direction) of the continuous inspected optical film laminate 10.Preferably, the checkup is performed by measuring a misalignment betweenrespective positions of an actually formed-slit and a reference line inthe X-direction, and a misalignment between respective positions of anedge (side edge) of the continuous inspected optical film laminate 10 inthe Y-direction, at two positions on upstream and downstream sides ofslitting positions where slits are to be formed in the continuousinspected optical film laminate 10 (position of the slitting unit 150).For example, each of the slitting position checkup units 160 may beprovided with a CCD camera to pick up and process an image of an area ofthe actually formed-slit and the edge of the continuous inspectedoptical film laminate 10. The reference lines are preset in each of theimage-pickup regions (camera field of view). Each of the positions ofthe actually formed-slit and the edge of the continuous inspectedoptical film laminate 10 is determined by a difference in contrastwithin the acquired image. Then, a distance (misalignment) between eachof the positions of the actually formed-slit and the edge of thecontinuous inspected optical film laminate 10, and the position of acorresponding one of the preset reference lines is calculated, and aposition and an inclination angle of the slitting unit 150 is correctedon the upstream or downstream side in the feed direction of thecontinuous inspected optical film laminate 10, based on the calculateddistance (misalignment). More specifically, as shown in FIG. 5, Steps 3,4 and 7 are performed under a condition that the continuous inspectedoptical film laminate 10 is fed in a tensioned state. Further, in Step5, a slit is formed in the continuous inspected optical film laminate10. Then, using the two slitting position checkup units 160, it isdetermined whether there is a misalignment between an actually formedslitting position in the continuous inspected optical film laminate 10and a corresponding slitting position calculated by the control unit400. If there is any misalignment, it is corrected in Steps 6 and 8, forexample, in the following manner.

A misalignment between an actually formed slitting position in thecontinuous inspected optical film laminate 10 and a correspondingreference slitting position may be determined and corrected in thefollowing process.

(1) Images of areas of an actually formed slit (X) and two edges (Y1,Y2) in the continuous inspected optical film laminate 10 are picked upby the CCD camera of the slitting position checkup unit 160, and thepicked-up image is processed to measure respective positions of theactually formed slit (X) and the edges (Y1, Y2) based on a differencesin contrast within the images.

(2) A reference slit formation position extending in the Y direction ispre-set at a position intermediate between an upstream reference linepre-set in an image pickup region of the upstream slitting positioncheckup unit 160 to extend in the Y-direction, and a downstreamreference line pre-set in an image-pickup region of the downstreamslitting position checkup unit 160 to extend in the Y direction, anddata γ representing a distance between the upstream and downstreamreference lines is pre-stored in the storage device 420 via theinformation processing device 410. Furthermore, two upstream anddownstream reference lines each extending in the X direction are pre-setin respective ones of the image-pickup regions of the upstream anddownstream slitting position checkup units 160.

(3) A correction value a of a slitting position and a correction value δof a slitting angle are calculated based on the reference lines and themeasured slitting position (X) and the measured edge positions (Y1, Y2)of the continuous inspected optical film laminate 10. The correctionvalue α of the slitting position of the continuous inspected opticalfilm laminate 10 is a measured misalignment α, i.e., a misalignment αbetween the actually formed slitting position (X) and the downstreamreference line extending in the Y direction. The correction value δ ofthe slitting angle can be calculated according to the following formula,based on misalignments (β1, β2) with respect to respective ones of theupstream and downstream reference lines each extending in the Xdirection, i.e., misalignments each measured in a respective one of thetwo image-pickup regions as a distance from the edge position of thecontinuous inspected optical film laminate 10 in the Y direction.

$\delta = {\cos^{- 1}\left\{ \frac{\gamma}{\sqrt{\gamma^{2} + \left( {\beta_{1} - \beta_{2}} \right)^{2}}} \right\}}$

(4) The correction values (α, δ) obtained based on the measured andcalculated data to instruct the slitting unit 150 to perform an angularcorrection by δ and a positional correction by α in the X direction soas to be aligned with the reference slitting position extending in the Ydirection are stored in the storage device 420.

(5) In advance of a next operation of forming a slit in the continuousinspected optical film laminate 10, based on the stored correctionvalues (α, δ), the control unit 400 instructs the cutting unit 150 toperform a correction in the feed direction and an angler correction in acrosswise direction with respect to the feed direction.

(6) After the corrections, the cutting unit 150 operates to form a nextslit in the continuous inspected optical film laminate 10.

(Lamination of Normal Polarizing Sheet Xα to Liquid-Crystal Panel)

A first feature of the system for continuously manufacturingliquid-crystal display element using the information storage/readoutdevice according to the above embodiment, which comprises the roll R ofthe continuous inspected optical film laminate 10 provided with theidentification means or indicia 20, and the information storage mediumwhich stores therein the slitting position information 80 for thecontinuous inspected optical film laminate 10 to be read out therefromin accordance with reading of the identification means or indicia 20, isin that, in advance of an operation of laminating to a liquid-crystalpanel W the normal polarizing sheet Xα cut into a given lengthcorresponding to the liquid-crystal panel W, from the continuousinspected optical film laminate 10 being fed, only the defectivepolarizing sheet Xβ cut from the continuous inspected optical filmlaminate 10 being fed can be removed by the removal unit 190, withoutinterrupting the feeding of the continuous inspected optical filmlaminate 10. A second feature of the system for continuouslymanufacturing liquid-crystal display element using the informationstorage/readout device according to the above embodiment, is in thatonly the normal polarizing sheet Xα cut into the given lengthcorresponding to the liquid-crystal panel W can be fed to the laminationunit 200 for lamination to the liquid-crystal panel W in the laminationstation, by the carrier film take up drive mechanism 210, withoutinterrupting the feeding of the continuous inspected optical filmlaminate 10, which is unimaginable in the discrete sheet or discretesheet-based liquid-crystal display element manufacturing process. Theuse of the information storage/retrieval sub-system in a liquid-crystaldisplay element production process undoubtedly makes it possible todrastically increase/enhance a speed and accuracy of lamination betweenthe normal polarizing sheet Xα and the liquid-crystal panel W.

(Conveyance of Liquid-Crystal Panel)

Before specifically describing the lamination unit 200 including thepair of lamination rollers adapted to be moved closer to and away fromeach other in vertical direction, so as to laminate the normalpolarizing sheet Xα cut into a given length corresponding to aliquid-crystal panel W, to the liquid-crystal panel W, an outline of theliquid-crystal panel conveyance unit 300 for conveying theliquid-crystal panel W to be laminated with the normal polarizing sheetXα cut into the given length corresponding to the liquid-crystal panelW, from the continuous inspected optical film laminate 10 being fed willbe described below. For example, in a liquid-crystal display element fora widescreen television having a diagonal screen size of 42 inches, arectangular-shaped liquid-crystal panel W has a size of 540 to 560 mmlength×950 to 970 mm width, as shown in FIG. 1. In a liquid-crystaldisplay element production process, an outer periphery of theliquid-crystal panel W is slightly cut in a wiring stage includingmounting of electronic components. Alternatively, the liquid-crystalpanel W may be in advance cut before it is conveyed to the laminationline. A plurality of the liquid-crystal panels W are taken out of amagazine having a large storage capacity, one-by-one, by aliquid-crystal-panel supply apparatus, and conveyed to the laminationunit 200 for lamination with respective ones of the normal polarizingsheets Xα, by the conveyance apparatus 300, while being adjusted at evenintervals and a constant conveyance speed, for example, via acleaning/polishing process. The normal polarizing sheet Xα is cut fromthe continuous inspected optical film laminate 10 to have a sizeslightly less than that of the liquid-crystal panel W. As shown in FIG.13, in a final stage of sequential conveyance of a plurality of theliquid-crystal panels W to the lamination station B, in synchronizationwith feeding of the normal polarizing piece Xα, the liquid-crystal panelconveyance unit 300 has a position or panel-posture control mechanismwhich comprises a pre-alignment unit 310, a final-alignment unit 320, afinal conveyance unit 330 for conveyance to the lamination unit, and apanel-edge detection unit 340 for detecting a reading edge of each ofthe liquid-crystal panels W.

FIG. 13 is a schematic diagram showing a part of the system forcontinuously manufacturing liquid-crystal display elements using theinformation storage/readout device according to the above embodiments,wherein, before the normal polarizing sheet Xα cut into the given lengthcorresponding to the liquid-crystal panel W, from the continuousinspected optical film laminate 10, is laminated to the liquid-crystalpanel W, and wherein the control unit 400 operates to control each ofthe pre-alignment unit 310, the final-alignment unit 320, the finalconveyance unit 330 and the panel-edge detection unit 340 of theliquid-crystal panel conveyance unit 300 based on the encodedinformation read from the continuous web of optical film by theidentification means reading unit 120, to convey the liquid-crystalpanel W while adjusting the position or the posture thereof. FIG. 14 isa schematic diagram showing the lamination unit 200 for lamination ofthe polarizing sheets to the liquid crystal panel W, together with theedge detection unit 220 for detecting a leading edge of the normalpolarizing sheet Xα cut into the given length corresponding to theliquid-crystal panel W, from the continuous inspected optical filmlaminate 10 illustrated in FIG. 13, and the position orstraight-ahead-posture detection unit 230 for assuring that the normalpolarizing sheet Xα is oriented in the feed direction.

Preferably, the normal polarizing sheet Xα is fed to the lamination unit200 in the lamination station B at a constant speed by the continuouscarrier film 14. As shown in FIG. 13 or 14, at the lamination station B,only the continuous carrier film 14 is peeled by having the carrier filmbent at an acute angle, by the carrier film take up drive mechanism 210,via a peeling plate 211. By having the continuous carrier film bent atan acute angle, the adhesive layer of the normal polarizing sheet Xα canbe gradually exposed. This makes it easy to align the leading edge ofthe liquid crystal panel W with the leading edge of the normalpolarizing sheet Xα when the leading edge of the normal polarizing sheetXα is slightly exposed. As shown in FIG. 13, the leading edge of thenormal polarizing sheet Xα is fed to appear at the gap between the pairof lamination rollers of the lamination unit 200 located in spaced apartrelation to each other, and detected by the edge detection unit 220.Although the normal polarizing sheet Xα is fed while being maintained onthe continuous carrier film 14, the normal polarizing sheet Xα is lesslikely to be accurately fed with a posture where an angle θ of the feeddirection with respect to a lengthwise direction of the continuouscarrier film 14 becomes zero. Therefore, respective displacements of thenormal polarizing sheet Xα in the feed direction and the directionperpendicular to the feed direction are measured, for example, bypicking up and processing an image thereof using a CCD camera of theposition or straight-ahead-posture detection unit 230. Then, themeasured displacements are represented in terms of X, Y and θ, and thecalculated data is stored in the storage device 420 by the control unit400.

Then, the plurality of liquid-crystal panels are sequentially suppliedfrom the liquid-crystal panel-supply apparatus including a magazine forliquid-crystal panels, illustrated in FIG. 4, at even intervals and aconstant speed. The liquid-crystal panels supplied one-by-one aresubjected to the posture control by the liquid-crystal panel conveyanceunit 300 illustrated in FIG. 13. As for this posture control, refer toFIG. 10. Each of the liquid-crystal panels is positioned by thepre-alignment unit 310, in such a manner as to allow lengthwise andwidthwise directions thereof to be aligned with respective ones of aconveyance direction of a conveyance path and a direction perpendicularto the conveyance direction. The positioned liquid-crystal panel isconveyed to and placed on the final-alignment unit 320. Thefinal-alignment unit 320 includes an alignment table 321 adapted to beturned by a drive mechanism under a control of the control unit 400. Theleading edge of the liquid-crystal panel placed on the alignment tableis detected by the panel-edge detection unit 340. The position of thedetected leading edge of the liquid-crystal panel is crosschecked with areference lamination position stored in the storage device 420,specifically, the calculation data represented in terms of X, Y and θ torepresent the posture of the normal polarizing sheet Xα to be laminatedto the liquid-crystal panel. For example, the displacement between theleading edge of the liquid-crystal panel and the reference laminationposition is measured using an alignment mark of the liquid-crystal panelillustrated in FIG. 1 to calculate an angular displacement θ, and thealignment table 321 having the liquid-crystal panel placed thereon isturned by the angular displacement θ. Then, the alignment table 321 isconnected to the final conveyance unit 330 for conveyance to thelamination station B. The liquid-crystal panel is conveyed to thelamination station B while keeping the same posture, by the finalconveyance unit 330. The leading edge of the liquid-crystal panel isaligned with the leading edge of the normal polarizing sheet Xα, andrespective leading ends of the liquid-crystal panel and the normalpolarizing sheet Xα are superimposed on each other. In a final stage,the normal polarizing sheet Xα and the liquid-crystal panel W in alignedrelation with each other are conveyed by the pair of lamination rollers,while being nipped therebetween. In this manner, a liquid-crystaldisplay element is completed.

Each of the normal polarizing sheets Xα is fed to the lamination unit200 in integral relation with the continuous carrier film 14, with thecontinuous inspected optical film laminate 10 being fed in a tensionedmanner, so that the peripheral edge of the normal polarizing sheet Xα isless likely to be bent or sagged. Thus, there is no risk of theoccurrence of bowing and sagging in the normal polarizing sheet Xα. Thismakes it possible to facilitate an operation of adjusting a posture ofthe liquid-crystal panel to conform to that of the normal polarizingsheet Xα fed to the lamination station B, and manufacture liquid-crystaldisplay elements at a higher speed with enhanced accuracy. The abovemethod and system can hardly be applied to the discrete sheet-basedliquid-crystal display element manufacturing process where, afterpeeling a releasable liner from each of a plurality of discrete sheetsto expose an adhesive layer, and suction-feeding each of the discretesheets to a lamination position, the discrete sheet is superimposed on aliquid-crystal panel while adjusting a position thereof with respect toa liquid-crystal panel, and laminated to the liquid-crystal panel tocomplete a liquid-crystal display element. As above, the system forcontinuously manufacturing liquid-crystal display element premised onthe use of an information storage/readout device comprising aninformation storage medium 800 storing therein slitting positioninformation 80 created based on a position of a defect detected by apreliminary inspection of an continuous polarizing composite film whichthe adhesive layer is not yet formed 11′ or an continuous polarizingcomposite film including adhesive layer 11 to indicatedefective-polarizing-sheet slitting positions defining a defectivepolarizing sheet, and normal-polarizing-sheet slitting positionsdefining a normal polarizing sheet, in the continuous inspected opticalfilm laminate 10 comprising a continuous polarizing composite film 11including an adhesive layer having a width conforming to a long or shortside of a liquid-crystal panel formed in a given size, and a continuouscarrier film 14 releasably laminated on the adhesive layer, wherein eachof the defective polarizing sheet-slitting position and the normalpolarizing sheet-slitting position is defined as a line extending in awidthwise direction of the continuous inspected optical film laminate10; and roll R of the continuous inspected optical film laminate 10which is provided with an identification means or indicia 20 associatedwith the slitting position information 80.

5. Creation of Slitting Position Information 80 for Continuous InspectedOptical Film Laminate 10

FIG. 15 is a table showing types and data content of the identificationmeans or indicia 20 to be provided on the continuous inspected opticalfilm laminate 10, in the embodiments of the present invention. Theidentification means or indicia 20 may be used in the form ofone-dimensional or two-dimensional code, IC tag or the like, and mayinclude data, such as a lot number, indicative of each continuousinspected optical film laminate 10 subjected to a defect inspection foran continuous polarizing composite film which the adhesive layer is notyet formed 11′ or an continuous polarizing composite film includingadhesive layer 11 thereof.

(Creation of Slitting Position Information 80)

FIG. 16 is a schematic diagram showing a process of creating theslitting position information 80 for the continuous inspected opticalfilm laminate 10, by calculating defective-polarizing-sheet slittingpositions defining a defective or defect-containing polarizing sheet Xβand normal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet Xα, based on the position of a defectcontained in the continuous polarizing composite film on which theadhesive layer is not yet formed 11′ or the continuous polarizingcomposite film including adhesive layer 11, in a method for producingthe information storage/readout device, according to one embodiment ofthe present invention. FIGS. 17 to 19 is a flowchart showing anotherprocess of creating the slitting position information 80 for thecontinuous inspected optical film laminate 10, by calculatingdefective-polarizing-sheet slitting positions defining a defective ordefect-containing polarizing sheet and normal-polarizing-sheet slittingpositions defining a normal or defect-free polarizing sheet, based onthe position of a defect contained in the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ or thecontinuous polarizing composite film including adhesive layer 11.Preferably, the information storage medium 800 storing therein theslitting position information 80 may be comprised of a floppy disk, CD,DVD, a flash memory or a hard disk. While a single information storagemedium may be enough, a plurality of information storage media may beused to backup the slitting position information 80 in consideration ofa risk of data loss. It is to be noted that the embodiments in theschematic diagram of FIG. 16 and the flowcharts of FIGS. 17 to 19 areshown only by way of illustration.

The control unit 700 functions to operate the information processingdevice 710 and the storage device 720 to process image data from theimage reading device 581 of the inspection unit 580 in association withthe distance measurement data relating to the feed distance measuredfrom the leading edge of the continuous polarizing composite film onwhich the adhesive layer is not yet formed 11′ or the continuouspolarizing composite film including adhesive layer 11 (the two type ofcontinuous polarizing composite films will hereinafter be referredcollectively as “continuous polarizing composite film 11”) by the lengthmeasurement device having an incorporated encoder 570 or 570′incorporating the encoder, so as to create position data relating to theposition of a defect contained in the continuous polarizing compositefilm, and then store the position data in the storage device 720. Then,the control unit 700 operates to determine a defective region Xβ and anormal region Xα in the continuous polarizing composite film 11, basedon the position data relating to the detected defect position. Further,based on the defective and normal regions of the continuous polarizingcomposite film 11, the control unit 700 operates to create slittingposition information 80 indicative of defective-polarizing-sheetslitting positions defining a defective polarizing sheet Xβcorresponding to the defective region Xβ, and normal-polarizing-sheetslitting positions defining a normal polarizing sheet Xα correspondingto the normal region Xα, in the continuous polarizing composite film 11.The slitting position information 80 is indicative of a plurality ofpositions at which respective ones of a plurality of slits are to beformed in the continuous inspected optical film laminate 10. In thesystem for continuously manufacturing liquid-crystal display elements 1,the slitting unit 150 operates to form the slits in the continuousinspected optical film laminate 10 being fed, along a directionperpendicular to the feed direction thereof from a surface opposite tothe continuous carrier film 14 to a depth reaching a surface of thecontinuous carrier film 14 adjacent to the adhesive layer. Under thecontrol of the control unit 700, the created slitting positioninformation 80 is temporarily stored in the storage device 720, and thenstored in the information storage medium 800. In order to backup theslitting position information 80, it may be stored in a plurality ofinformation storage media. The slitting position information 80 isassociated with the identification means or indicia 20 to be provided onthe continuous inspected optical film laminate 10. In the system forcontinuously manufacturing liquid-crystal display elements 1 illustratedin FIG. 4, the slitting position information 80 is read out from theinformation storage medium 800 or the storage device 420 in accordancewith the results of reading the identification means or indicia 20 bythe identification means reading unit 120, and processed by theinformation processing device 410 of the control unit 400.

The description will now be made based on the schematic diagram of FIG.16 and the flowcharts of FIGS. 17 to 19. The schematic diagram of FIG.16 shows a state when the continuous inspected optical film laminate 10is being continuously fed in a rightward direction by the feed rollers591, 592 of the carrier film feed unit 590. The flowcharts of FIGS. 17to 19 show specific steps from an initial step of, before the continuouscarrier film 14 is releasably laminated on one of opposite surfaces ofthe continuous polarizing composite film 11, and, optionally, thecontinuous surface protection film 13 is releasably laminated on theother surface of the continuous polarizing composite film 11, under thecontrol of the control unit 700, detecting a defect contained in thecontinuous polarizing composite film 11 by the inspection unit, tocreate the slitting position information 80 for the continuous inspectedoptical film laminate 10, based on the defect position, to a final stepof, under the control of the control unit 700, winding the continuousinspected optical film laminate 10 provided with the identificationmeans or indicia 20 by the optical film laminate take up drive mechanism630 to form the roll R of the continuous inspected optical film laminate10.

In either process, in Step 1, the control unit 700 operates to cause thelamination drive mechanism 560/the provisional optical film laminatefeed drive mechanism 560′ and the optical film laminate take up drivemechanism 630 to feed the continuous polarizing composite film 11. InStep 2, the control unit 700 operates to cause the inspection unit 560including the image reading device 580 to detect the position of adefect contained in the continuous polarizing composite film, and storethe detected defect position in the storage device 720 together with thetype and size of the detected defect. In Steps 3 and 4, the control unit700 operates to determine the relationship between the length of thepolarizing sheet and the length (xα) corresponding to that of a normalregion. The technique of determining the relationship is as follows.

In Step 3, the control unit 700 operates to cause the informationprocessing device 710 to calculate the distance X between the referenceposition and the defect position in the continuous polarizing compositefilm 11 being fed, and store the calculated distance X in the storagedevice 720. For example, as shown in FIG. 16, the distance X is adistance between the position of the carrier film feed unit 590 (thereference position of the continuous polarizing composite film 11) andthe position of the inspection unit 580/image-reading device 581 (thedefect position).

In Step 4, the control unit 700 further operates to cause theinformation processing device 710 to subtract a length (xα)corresponding to that of the normal region from the distance X to obtaina distance (x−xα)=x′, and then store the distance x′ in the storagedevice 70. The length (xα) corresponding to that of the normal region ofthe continuous optical film is set based on the size of a liquid-crystalpanel, and pre-stored in the storage device 670, by a system manager.Then, the control unit 700 operates to cause the information processingdevice 710 to determine whether the calculated distance x′ is greater orless than the length (xα) corresponding to that of the normal region ofthe continuous polarizing composite film 11.

Specifically, if x′ (or x″) in FIG. 16>xα, it means that the normalregion (Xα) of the continuous polarizing composite film 11 can beensured. Thus, the control unit 700 operates to determine a position Bspaced apart from the reference position A (first slitting position) onan upstream side by the length (xα), as a next slitting position forcutting a normal polarizing sheet Xα corresponding to the normal region,and then instructs the lamination drive mechanism 560/the provisionaloptical film laminate feed drive mechanism 560′ and the optical filmlaminate take up drive mechanism 630 to feed the continuous polarizingcomposite film 11 in a tensioned manner by the length (xα) of the normalregion. The value of the length (xα) constitutes as a part of theslitting position information for forming a normal polarizing sheet Xαcorresponding to the normal region in the continuous polarizingcomposite film 11. After determining the second slitting position(position B), a third slitting position (position C) is determined inthe same manner, and the continuous polarizing composite film 11 is fedunder tension by the length (xα) of the normal region.

On the contrary, if x′≦xα, i.e., X′″ in FIG. 16≦xα, it means that thenormal region (Xα) of the continuous polarizing composite film 11 cannotbe ensured. In this case, the region which can be taken in thecontinuous polarizing composite film 11 having a length (xβ) is adefective region. Thus, the control unit 700 operates to cause theinformation processing device 710 to add a certain distance x0 to x′(x′″ in FIG. 16) so as to derive a length (x′+x0)=xβ corresponding tothe defective region Xβ. Specifically, a position E spaced apart fromthe position D on the upstream side by the length xβ is a defectiveregion corresponding to the defective region. The control unit 700instructs the lamination drive mechanism 560/the provisional opticalfilm laminate feed drive mechanism 560′ and the optical film laminatetake up drive mechanism 630 to feed the continuous polarizing compositefilm 11 under tension by the length (xβ) of the defective region. Thevalue of the length (xβ) constitutes a part of the slitting positioninformation for forming a defective polarizing sheet Xβ corresponding tothe defective region in the continuous polarizing composite film 11.

Specifically, the control unit 700 operates to calculate the following(a) and (b) to create slitting position information 80 indicative of aplurality of positions at which respective ones of a plurality of slitsare to be formed to allow normal polarizing sheets Xα and defectivepolarizing sheets Xβ to be formed in the continuous inspected opticalfilm laminate 10 which is fed during the liquid-crystal display elementmanufacturing process:

-   -   (a) a distance (Xα) to a next slitting position, if x′>xα; and    -   (b) a distance (x′+x0=Xβ) to a position for forming a next cut        line, if x′≦xα, and then operates to store the slitting position        information in the storage device 720.

If a length (x′+x0=xβ) corresponding to the defective region becomesequal to the length (xα) corresponding to the normal region, i.e., if(x′+x0)=(xα), the control unit 700 cannot identify or discriminate thenormal region (Xα) from the defective region (Xβ). This means that thedefective region (Xβ) cannot be recognized by the length (xβ) thereof.Thus, for example, in the system for continuously manufacturingliquid-crystal display element illustrated in FIG. 4, each of the normalregion (Xα) and the defective region (Xβ) cannot be discriminated fromeach other based on the distance measurement data as the feed distanceof the continuous inspected optical film laminate 10, so that theslitting position information 80 created based on the distancemeasurement data (x′+x0) inevitably becomes imperfect. It is assumedthat such a situation occurs when the position of a defect contained inthe continuous polarizer film is infinitely close to a next slittingposition in the continuous inspected optical film laminate 10, or whenvarious defects are distributed over a length (xα) corresponding to thenormal region.

Therefore, in Step 5, if (x′+x0) becomes equal to (xα), the control unit700 functions to have the information processing device 710 perform acalculation based on at least one of the following techniques to createinformation for identifying or discriminating the normal region (Xα)over the defective region (Xβ).

In Step 5 illustrated in FIG. 17, even if, as a result of calculation ofthe information processing device 710, the distance (x′+x0) to a nextslitting position becomes equal to the length (xα) corresponding to thenormal region, the region between the two position is not a normalregion (Xα). In order to allow such a region to be recognized as thedefective region, there is provided defective-sheet identificationinformation Xγ as illustrated in FIG. 20 in the form of, for example, avalue “0” and a value “1” which may be associated, respectively, withthe slitting position information indicative of a next slitting positioncorresponding to the normal region, and slitting position informationindicative of a next slitting position corresponding to the defectiveregion. Alternatively, in Step 5 illustrated in FIG. 18, a processingalgorithm of the information processing device 710 may be configured,if, as a result of calculation of the information processing device 710,a distance (x′+x0) to a next slitting position becomes equal to thelength (xα) corresponding to the normal region, to allow the distance tothe next slitting position to become (x′+x0′), wherein x0′>x0, and storethe distance (x′+x0′device 720. As shown in FIG. 21, this processingalgorithm is configured to calculate the next slitting position as(x′+x0′) different from xα to allow a region having the length (x′+x0′)to be identified or discriminated against the normal region (Xα). InStep 5 illustrated in FIG. 19, a processing algorithm of the informationprocessing device 710 is configured if, as a result of calculation ofthe information processing device 710, a distance (x′+x0) to a nextslitting position becomes equal to the length (xα) corresponding to thenormal region, to allow the distance to the next slitting position tobecome [(x′+x0)/m], wherein m=2 or more, preferably 2 or 3, and storethe distance [(x′+x0)/m] in the storage device 720. As with the processshown in FIG. 18, the processing algorithm in FIG. 22 is configured tocalculate the next slitting position as [(x′+x0)/m] different from xα toallow a region having the length [(x′+x0)/m] to be identified ordiscriminated against the normal region (Xα).

The above processes are summarized as follows. As a process of creatinginformation for identifying or discriminating the defective and thenormal polarizing sheets Xα, Xβ one from the other, any one of thefollowing processes may be employed:

-   -   (1) To create defective-sheet identification information Xγ as        information for identifying or discriminating a region having a        length (x′+x0) calculated by the information processing device        710 and the normal region (Xα);    -   (2) To calculate a distance to a next slitting position by the        information processing device 710, as a distance (X′+x0′)        (wherein x0′>x0) which is different from the length of the        normal polarizing sheet (Xα); and    -   (3) To calculate a distance to a next slitting position by the        information processing device 610, as a distance [(x′+x0)/m]        (wherein m=2 or more) which is different from Xα.

Particularly, in cases where the process (2) or (3) is employed,(x′+x0)=(xα) is changed to (x′+x0′)≠xα or [(x′+x0)/m]≠ xα through theprocessing illustrated in FIG. 18 or 19. Thus, the next slittingposition can be used as information indicative of the defectivepolarizing sheet Xβ identifiable or discriminatable from the normalregion.

Then, in either process, in Step 6, the control unit 700 functions tooperate the information processing device 710 to determine a lengthbetween the reference position A and the next slitting position, basedon the calculation result in Steps 4 and 5. In the process (2) or (3),the control unit 700 operates to cause the information processing device710 to store the length to the next slitting position determined in Step7, in the storage device 720. Differently, in the process (1), thecontrol unit 700 operates to cause the information processing device 710to store the length to the next slitting position in association withthe defective-sheet identification information Xγ. In either process, inStep 6, the control unit 700 operates to cause the informationprocessing device 710 to, based on the next slitting position stored inthe storage device 720 in Step 7, create slitting position information80 indicative of slitting positions with respect to the leading edge ofthe continuous inspected optical film laminate 10, in sequence. Ineither process, in Step 10, the slitting position information is storedin the information storage medium 800 via the storage device 720.

In either process, as shown in FIG. 16, in Step 7, the continuouscarrier film 14 is releasably laminated on one of opposite surfaces ofthe continuous polarizer film 11 by the carrier film feed unit 590, and,optionally, the continuous surface protection film 13 is releasablylaminated on the other surface of the continuous polarizer film 11 bythe surface protection film feed unit 640, to form a continuousinspected optical film laminate 10. In either process, in Step 8, thecontrol unit 700 operates to cause the providing device 720 to mark theidentification means or indicia 20 created by the information processingdevice 710 in association with the slitting position information 800 inStep 6, on the continuous inspected optical film laminate 10 produced ina certain production lot, etc. Through the above process, the continuousinspected optical film laminate 10 provided with the identificationmeans or indicia 20 is produced.

Finally, in Step 9, the control unit 700 functions to operate thelamination drive mechanism 560 and the optical film laminate take updrive mechanism 630 to wind the continuous inspected optical filmlaminate 10 provided with the identification means or indicia 20 toproduce the roll R. Examples of the slitting position information 80 andthe identification means or indicia 20 are shown in FIGS. 20 to 22.

6. Outline of Inspection Method and Device

FIG. 23 is a table showing an inspection device for inspecting a defectcontained in an continuous polarizing composite film which the adhesivelayer is not yet formed 11′ or an continuous polarizing composite filmincluding adhesive layer 11, a type of defect and a detection method, inone embodiment of the present invention. Typically, a defect containedin a continuous polarizing composite film which the adhesive layer isnot yet formed 11′ or a continuous polarizing composite film includingadhesive layer 11 is inspected in the inspection station M, whilecontinuously feeding the continuous polarizing composite film. Theinspection station may include at least the following three types ofinspection devices.

A first inspection unit is a defect inspection device designed to detecta surface of a continuous polarizing composite film 11′ or a continuouspolarizing composite film 11, by means of reflected light. As shown inFIG. 23, a detectable defect is limited to irregularities andflaw/undulation in a surface detectable by a CCD camera.

A second inspection device is a defect inspection device designed todetect a light which has transmitted through the continuous polarizingcomposite film 11′ or a continuous polarizing composite film 11. Thelight from a light source is projected at a right angle to the surfaceof the film 11 or 11′, and the light transmitted through the film isreceived by an optical inspection unit to detect a defect existing inthe continuous polarizing composite film 11′ or the continuouspolarizing composite film 11, as a shade. As shown in FIG. 23, adetectable defect is internal foreign substances, internal pores, etc.

A third inspection device is a defect inspection device operable undercross-Nicol conditions. Along with the practical use of this defectinspection device, accuracy in defect inspection of continuouspolarizing composite films has been drastically improved. Generally,there is a strong tendency to accept only such continuous polarizingcomposite films which has passed defect inspection under the cross-Nicolconditions, for large-size liquid-crystal display elements. Aninspection process is as follows. Firstly, the continuous polarizingcomposite film on which the adhesive layer is not yet formed 11′ or thecontinuous polarizing composite film including adhesive layer 11 whichis a subject for inspection, and a corresponding polarization filter,are arranged to have absorption axes thereof set in a cross-Nicolarrangement. Then, the light is projected thereto from a light source,and transmitted light is observed. Through the observation, a defectcontained in the continuous polarizing composite film 11′ or thecontinuous polarizing composite film 11 is detected as a bright spot.More specifically, the third inspection device is a defect inspectiondevice designed such that a polarization filter is disposed just beforean optical sensor unit in such a manner as to allow an absorption axisthereof to extend at a right angle with respect to an absorption axis ofthe continuous polarizing composite film which the adhesive layer is notyet formed 11′ or the continuous polarizing composite film includingadhesive layer 11, and light is emitted from a light source to theoptical sensor unit while passing through the continuous polarizingcomposite film 11′ or the continuous polarizing composite film 11 at anincidence angle perpendicular or oblique thereto, to detect any defectexisting in the continuous polarizing composite film on which theadhesive layer is not yet formed 11′ or the continuous polarizingcomposite film including adhesive layer 11, as a bright spot. As shownin FIG. 23, the inspection method can detect substantially all defects,except surface irregularities.

Although the present invention has been described in connection withpreferred embodiments thereof, it will be appreciated that variouschanges and modifications will be made by those skilled in the artwithout departing from the spirit and scope of the invention, defined inthe appended claims, and legal equivalents of the appended claims may besubstituted for elements thereof. Accordingly, the present invention isnot limited to the specific embodiments disclosed as the best mode forcarrying out the invention, but intended to cover all embodimentsincluded within the scope thereof.

1. A method for producing an information storage/readout device for usein a system for continuously manufacturing liquid-crystal displayelements, the system for continuously manufacturing liquid-crystaldisplay elements being configured to work with a roll of a continuousoptical film laminate which comprises a continuous polarizing compositefilm including an adhesive layer and having a width conforming to a longor short side of a liquid-crystal panel formed in a given size, and acontinuous carrier film releasably laminated on the adhesive layer, thesystem for continuously manufacturing liquid-crystal display elementsbeing configured to form a plurality of slits in the continuous opticalfilm laminate fed out from the roll, along a direction perpendicular toa longitudinal direction thereof, to make it possible to sequentiallycut a plurality of polarizing sheets each having a given lengthcorresponding to the long or short side of the liquid-crystal panel fromthe continuous optical film laminate and to laminate the sheets torespective ones of a plurality of liquid-crystal panels so as tocontinuously manufacture liquid-crystal display elements, theinformation storage/readout device comprising an information storagemedium which stores therein slitting position information created basedon a position of a defect detected by an inspection of a continuouspolarizing composite film included in a continuous optical film laminateto indicate defective-polarizing-sheet slitting positions defining adefective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in the continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification indicia, the production methodcomprising the steps of: laminating a continuous protective film on atleast one of opposite surfaces of a continuous polarizer to form ancontinuous polarizing composite film on which the adhesive layer is notyet formed; inspecting the continuous polarizing composite film todetect any defect existing in the continuous polarizing composite filmon which the adhesive layer is not yet formed; creating, based on theposition of the defect in the continuous polarizing composite film onwhich the adhesive layer is not yet formed, the slitting positioninformation indicative of the normal polarizing sheet-slitting positionsand the defective polarizing sheet-slitting positions definingrespective ones of the normal polarizing sheet and the defectivepolarizing sheet in a direction perpendicular to a longitudinaldirection of the continuous polarizing composite film on which theadhesive layer is not yet formed; releasably laminating a continuouscarrier film to the continuous inspected polarizing composite film onwhich the adhesive layer is not yet formed through an adhesive layer toform the continuous inspected optical film laminate; storing theslitting position information in a storage medium to thereby provide theinformation storage medium, in a manner usable by the systemcontinuously manufacturing to, during feeding of the continuousinspected optical film laminate, form a plurality of slits in thecontinuous inspected optical film laminate along a directionperpendicular to the longitudinal direction from a surface opposite tothe continuous carrier film to a depth reaching a surface of thecontinuous carrier film adjacent to the adhesive layer so as to make itpossible to cut the normal polarizing sheet and the defective polarizingsheet from the continuous inspected optical film laminate individually;creating the identification means in association with the slittingposition information and providing the identification means on thecontinuous inspected optical film laminate; and winding the continuousinspected optical film laminate provided with the identification means,without separating the defect-containing polarizing sheet from thedefect-free polarizing sheet, into a roll to provide the roll of thecontinuous optical film laminate.
 2. The method as defined in claim 1,wherein the step of forming the continuous inspected optical filmlaminate includes a sub-step of releasably laminating a continuoussurface protection film on the continuous inspected polarizing compositefilm at a surface opposite to the adhesive layer.
 3. The method asdefined in claim 1, wherein the step of detecting a defect contained inthe continuous polarizing composite film on which the adhesive layer isnot yet formed includes one or a combination of one or more of sub-stepsof primarily inspecting a surface of the continuous polarizing compositefilm on which the adhesive layer is not yet formed by means of reflectedlight, detecting light which has been projected from a light source andtransmitted through the continuous polarizing composite film on whichthe adhesive layer is not yet formed to detect any defect existing inthe continuous polarizing composite film on which the adhesive layer isnot yet formed as a shade, and arranging the continuous polarizingcomposite film on which the adhesive layer is not yet formed and apolarization filter to have absorption axes thereof set in a cross-Nicolarrangement followed by emitting light from a light source thereto andobserving light transmitted therethrough to detect a defect existing inthe continuous polarizing composite film on which the adhesive layer isnot yet formed as a bright spot.
 4. A method for producing aninformation storage/readout device for use in a system for continuouslymanufacturing liquid-crystal display elements, the system forcontinuously manufacturing liquid-crystal display elements beingconfigured to work with a roll of a continuous optical film laminatewhich comprises a continuous polarizing composite film including anadhesive layer and having a width conforming to a long or short side ofa liquid-crystal panel formed in a given size, and a continuous carrierfilm releasably laminated on the adhesive layer, the system forcontinuously manufacturing liquid-crystal display elements beingconfigured to form a plurality of slits in the continuous optical filmlaminate fed out from the roll, along a direction perpendicular to alongitudinal direction thereof, to make it possible to sequentially cuta plurality of polarizing sheets each having a given lengthcorresponding to the long or short side of the liquid-crystal panel fromthe continuous optical film laminate and to laminate the sheets torespective ones of a plurality of the liquid-crystal panels so as tocontinuously manufacture liquid-crystal display elements, theinformation storage/readout device comprising an information storagemedium which stores therein slitting position information created basedon the position of a defect detected by an inspection of a continuouspolarizing composite film included in a continuous optical film laminateto indicate defective-polarizing-sheet sheet slitting positions defininga defective or defect-containing polarizing sheet, andnormal-polarizing-sheet slitting positions defining a normal ordefect-free polarizing sheet, in the continuous inspected optical filmlaminate, and a roll of the continuous inspected optical film laminatewhich is provided with an identification indicia, the method comprisingthe steps of: preparing a roll of a continuous provisional optical filmlaminate which comprises a continuous polarizing composite film formedwith an adhesive layer, and a continuous provisional carrier filmreleasably laminated on the adhesive layer; peeling the continuousprovisional carrier film while feeding the continuous provisionaloptical film laminate out from the roll, to have adhesive layer on thecontinuous polarizing composite film exposed; inspecting a surface andinside of the continuous polarizing composite film having the exposedadhesive layer to detect a defect contained in the continuous polarizingcomposite film including adhesive layer; creating, based on a positionof the defect in the continuous polarizing composite film includingadhesive layer, the slitting position information indicative of thenormal polarizing sheet-slitting positions and the defective polarizingsheet-slitting positions defining respective ones of the normalpolarizing sheet and the defective polarizing sheet in a directionperpendicular to a longitudinal direction of the continuous polarizingcomposite film including adhesive layer; releasably laminating acontinuous carrier film on the exposed adhesive layer of the continuousinspected polarizing composite film to form the continuous inspectedoptical film laminate; storing the slitting position information in astorage medium to thereby form the information storage medium, in amanner usable by the continuous manufacturing system to, during feedingof the continuous inspected optical film laminate, form a plurality ofslits in the continuous inspected optical film laminate along adirection perpendicular to the longitudinal direction from a surfaceopposite to the continuous carrier film to a depth reaching a surface ofthe continuous carrier film adjacent to the adhesive layer so as to makeit possible to cut the normal polarizing sheet and the defectivepolarizing sheet from the continuous inspected optical film laminateindividually; creating the identification means in association with theslitting position information and providing the identification means onthe continuous inspected optical film laminate; and winding thecontinuous inspected optical film laminate provided with theidentification means, without separating the defect-containingpolarizing sheet from the defect-free polarizing sheet, into a roll toserve as the roll of the continuous optical film laminate.
 5. The methodas defined in claim 4, wherein the continuous provisional carrier filmhas a transferable adhesive layer formed by subjecting one surface ofthe continuous provisional carrier film to a releasing treatment,applying a solvent containing an adhesive to the treated surface, anddrying the solvent.
 6. The method as defined in claim 4, wherein thecontinuous carrier film is subjected to a releasing treatment at asurface which is to be laminated on the exposed adhesive layer of thecontinuous inspected polarizing composite film.
 7. The method as definedin claim 4, wherein the step of forming the continuous inspected opticalfilm laminate includes a sub-step of releasably laminating a continuoussurface protection film on a surface of the continuous inspectedpolarizing composite film on an opposite side of the adhesive layer. 8.The method as defined in claim 4, wherein the step of detecting a defectexisting in the continuous polarizing composite film including adhesivelayer comprises one or a combination of one or more of sub-steps ofprimarily inspecting a surface of the continuous polarizing compositefilm including adhesive layer by means of reflected light, inspectinglight which has been projected from a light source and transmittedthrough the continuous polarizing composite film including adhesivelayer to detect any defect existing in the continuous polarizingcomposite film including adhesive layer as a shade, and arranging thecontinuous polarizing composite film including adhesive layer and apolarization filter to have absorption axes thereof set in a cross-Nicolarrangement followed by emitting light from a light source thereto andobserving light transmitted therethrough to detect a defect contained inthe continuous polarizing composite film including adhesive layer as abright spot.